Zimmerman writes analytics-focused baseball and football articles for RotoWire. He also handles scouting and reporting for PrepBaseballReport.com and contributes to RoyalsReview.com, FanGraphs.com and BaseballHeatMaps.com. Jeff is also a two time FSWA award winner, including the 2016 Football Writer of the Year award.
February 23, 2017
Jeff Zimmerman looks for the traits that could determine which pitchers will struggle with an ERA greater than their ERA estimators. Is Shelby Miller doomed?
October 21, 2016
Jeff Zimmerman looks at aging curves for quarterbacks to pinpoint the age that signal callers begin to decline. It might be earlier than most assume.
October 8, 2016
Jeff Zimmerman took home a Tout Wars title, but it came down to one nail-biting Christian Yelich at-bat on the last day of the season. Find out how he did it.
October 8, 2016
Jeff Zimmerman walks through the process of evaluating the value for players replacing injured or suspended teammates and if it makes sense to draft them.
September 28, 2016
Jeff Zimmerman examines whether pairing a quarterback and kicker from the same team is a good draft strategy. The results surprised even him.
September 24, 2016
As the 2016 season winds down, Jeff Zimmerman reviews what fantasy owners should be doing now to prepare for 2017.
September 21, 2016
Jeff Zimmerman delves into the numbers to figure out just how much weight fantasy owners should give to the previous season when evaluating players.
September 9, 2016
Jeff Zimmerman analyzes player aging curves to determine when NFL running backs and wide receivers can be expected to decline. Is Julio Jones headed for a fall?
September 6, 2016
Jeff Zimmerman jumps into the deep pool of spin-rate data to find out what it means for pitchers and fantasy owners. What does spin rate tell us?
September 2, 2016
Jeff Zimmerman analyzes whether a player's second-half breakout is predictive for the following season. It is, but not in the way most assume.
August 27, 2016
Jeff Zimmerman reviews strategies for competing in September and how to best take advantage of things like innings limits and trades.
August 19, 2016
Jeff Zimmerman analyzes the exclusive club of starting pitchers who have hit the trifecta with GB, K, BB rates of 40, 20, 10 and explains what it means for fantasy owners.
August 18, 2016
Jeff Zimmerman delves into the numbers to determine whether talent or opportunity is better in predicting the success of rookie wide receivers and tight ends.
August 11, 2016
Jeff Zimmerman looks at players who have can contribute to fantasy teams with both power and speed, like the Twins' Eduardo Nunez.
August 4, 2016
Jeff Zimmerman delves into what to look for when deciphering a streak vs. a skills change for hitters. Is Daniel Murphy showing skills growth, or is he destined for significant regression?
July 27, 2016
Jeff Zimmerman analyzes the closer situations throughout the league and how the trade deadline could impact who closes this year and in 2017 for each team. Is Dellin Betances the future in New York?
July 16, 2016
Jeff Zimmerman analyzes how much off-field issues like birth and death impact a player's performance. Death seemed to affect Jean Segura in 2014. But what does that mean for others?
July 7, 2016
Jeff Zimmerman builds on last week's article that discussed player age and plate discipline to see which contact values might indicate a change in a player's performance.
July 1, 2016
Jeff Zimmerman looks at the relationship between a player's age and plate discipline, and perhaps it makes sense that Carlos Gomez's contact rate has nosedived this season.
June 22, 2016
Jeff Zimmerman looks at the last 30 days of stats to find players who are flying under the radar, like the Angels' Matt Shoemaker, and others who might be due for regression.
June 17, 2016
Jeff Zimmerman explores whether running backs selected early in the NFL Draft are any more productive than their late-round brethren. The results might surprise you.
June 15, 2016
Jeff Zimmerman examines batted-ball velocity and which players have experienced the effects of changing velocity from last year, like Jose Altuve.
June 10, 2016
Expanding on last week's article, Jeff Zimmerman looks at the success and failure rates of top prospects to try and determine how long it takes to make an impact in the majors.
June 3, 2016
Jeff Zimmerman looks at the success, and failure, rates of prospects since 1990, gleaning some important information for fantasy owners to consider. How much patience is warranted for the likes of Byron Buxton?
May 25, 2016
Jeff Zimmerman looks at the application of StatCast data and what it means for fantasy owners when batted-ball velocity changes for a hitter like Victor Martinez.
May 18, 2016
Jeff Zimmerman looks at every team's closer situation and who might benefit from deadline deals. Can Sean Doolittle get his job back in Oakland?
May 12, 2016
Jeff Zimmerman analyzes the exclusive club of starting pitchers who have hit the trifecta with GB, K, BB rates of 50, 20, 10 and explains what it means for fantasy owners.
May 4, 2016
Jeff Zimmerman analyzes pitchers who have seen a skills growth or a skills decline this season and what it means for fantasy owners. Why are Dallas Keuchel's strikeouts down this year?
April 28, 2016
Jeff Zimmerman analyzes hitters who have seen a skills growth or a skills decline this season and what it means for fantasy owners. Is time to give up on Justin Upton?
April 21, 2016
Jeff Zimmerman digs into the data to determine the value of spring training pitching velocity and whether cold weather impacts velocity. The results might surprise you.
April 14, 2016
Jeff Zimmerman discusses different approaches to FAAB bidding and how owners can help themselves by taking a few important steps, especially when it comes to closers.
April 7, 2016
Yes, it's early, but Jeff Zimmerman has his eye on some specific stats and themes that can pay dividends. Find out why he's so interested in Billy Hamilton's groundball rate.
April 1, 2016
Jeff Zimmerman looks at the park effects of Coors Field and whether the adage to start all hitters and bench all pitchers in Colorado actually makes sense.
March 24, 2016
Jeff Zimmerman's Tout league has some unique rules that forced him to develop an interesting draft strategy, netting him some high-priced pitchers like Max Scherzer.
March 17, 2016
Jeff Zimmerman discusses the pros and cons of targeting multi-position players in fantasy drafts, like the Yankees' Brian McCann.
March 9, 2016
Jeff Zimmerman explains why benching Mike Trout for Jayson Werth is the right move when you consider the pitchers each face.
March 3, 2016
Jeff Zimmerman analyzes what usually happens when players move from infield to outfield and what that means for Ian Desmond, the Rangers' new left fielder.
February 27, 2016
Jeff Zimmerman delves into the numbers to determine the age ace pitchers start to decline and what it means this season for starters like Adam Wainwright.
October 16, 2015
Jeff Zimmerman continues his review of his pre and mid-season predictions.
October 9, 2015
Jeff Zimmerman reviews his predictions for this season.
October 1, 2015
Does September performance predict anything? Jeff Zimmerman takes a look.
September 24, 2015
Jeff Zimmerman shows fantasy owners how best to start the prep work now for next season's drafts. It's time to start preparing.
September 2, 2015
Jeff Zimmerman looks at pitching prospects for 2016 you might have forgotten.
August 27, 2015
This year's disappointments could be next year's targets, writes Jeff Zimmerman, who lays out a host post-hype prospects to track for 2016.
August 20, 2015
Jeff Zimmerman looks back at his 2015 drafts and examines how he can better value pitchers with an eye toward 2016. Should we be optimistic about a pitcher like Robbie Ray?
August 13, 2015
Mark Teixeira, A-Rod and Albert Pujols are having big seasons. Jeff Zimmerman has tips on finding the next batch of over-30 bargains.
August 5, 2015
Jeff Zimmerman does the math to figure values for inactive players, including the Marlins' Giancarlo Stanton.
July 29, 2015
Jeff Zimmerman looks at power projections for some of baseball's aging sluggers, including the Angels' Albert Pujols.
July 22, 2015
Jeff Zimmerman crunches the numbers to look for second-half hitting stars.
July 16, 2015
Can Chris Archer keep this up? Jeff Zimmerman crunches the numbers using K%-BB% and something called R-squared to predict the second half.
July 1, 2015
Jeff Zimmerman on the pitchers with the most effective sinking fastballs.
June 24, 2015
Jeff Zimmerman looks at some of the top young pitchers in the game.
June 18, 2015
Jeff Zimmerman looks at some recent call-ups and what we can expect from their careers
June 11, 2015
Jeff Zimmerman on batted-ball velocity stats and what they can tell us about today's top hitters.
June 4, 2015
Jeff Zimmerman on using advanced stats to find waiver-wire values.
May 28, 2015
Jeff Zimmerman on Michael Wacha and other pitchers that have been more lucky than good this season.
May 20, 2015
Jeff Zimmerman analyzes batter vs. pitcher splits to find out what's really relevant and predictive for fantasy owners and daily game players.
May 14, 2015
Jeff Zimmerman looks at the predictive value of batted-ball velocity and why it might make Hanley Ramirez a buy-high candidate.
May 6, 2015
Jeff Zimmerman on whether it's time to be concerned about slow-starting Andrew McCutchen and others.
April 29, 2015
When should we start paying attention to early-season stats? Jeff Zimmerman offers some guidelines.
April 23, 2015
Jeff Zimmerman looks at deceptive early stats, including Adam Jones' otherworldly batting average.
April 15, 2015
Jeff Zimmerman analyzes the biggest gainers and decliners in fastball velocity this season, and he doesn't like what he sees from Koji Uehara's high-school fastball.
April 8, 2015
Jeff Zimmerman lets us in on the secret for the most underutilized stat in fantasy baseball, and how you can use it to your great advantage.
April 2, 2015
Jeff Zimmerman offers tips on how to evaluate players in the early going of the season, including how to figure out when a player is hurt rather than just slumping.
March 26, 2015
Jeff Zimmerman looks at whether spring-training steal rates can predict regulare-seasonr rates and how the Dee Gordon trade will impact the Dodgers and Marlins.
March 18, 2015
Looking for a breakout pitcher? Jeff Sullivan shares the key stat for targeting pitchers on the verge of breaking out, and he has the data to back it up.
March 12, 2015
Jeff Zimmerman's AL LABR draft strategy was to spread his dollars, and he ended up spending big on only one player, Jose Abreu.
March 4, 2015
Spring training stats don't mean much, and player information can he hard to find. Jeff Zimmerman outlines four important things to look for in spring training and, just as important, how to find them.
February 26, 2015
Jeff Zimmerman ranks setup men according to the number of saves they could get this season, and Philadelphia's Ken Giles might be the best bet.
September 25, 2014
Jeff Zimmerman looks back at his columns from 2014 to see the hits and misses, including his projected struggles for Evan Longoria.
September 19, 2014
Javier Baez has shown incredible power in the second half of 2014, but how much can he deliver in 2015? Jeff Zimmerman looks at the possibilities for Baez, and several others for next season.
September 11, 2014
Ken Giles has all of the tools to become a closer, but he needs the Phillies to find a taker for Jonathan Papelbon in order to ascend to the ninth-inning role in Philadelphia.
September 4, 2014
Are Kevin Gausman and the Orioles' starting pitchers undervalued? Jeff Zimmerman looks for potential starting pitcher pickups for the final weeks of the season.
August 28, 2014
Jason Hammel has struggled since being traded to Oakland. Jeff Zimmerman looks at Hammel's fall, and other second-half skill changes in this week's installment of The Saber's Edge.
August 21, 2014
Chris Carter has always shown a combination of impressive power and inconsistent contact skills, but is he finally putting all together in the in the second half? Jeff Zimmerman attempts to identify hitters having a breakout.
August 13, 2014
With an excellent curveball, Corey Kluber has had a full breakout in 2014. Jeff Zimmerman looks at the trends of the curve, and seeks out other pitchers with the potential to take a big leap forward.
August 6, 2014
In this week's column, Jeff Zimmerman uses available data to analyze significant shifts in power, including the decline of Jay Bruce this season.
July 31, 2014
Pitchers lose velocity as they age, but how much of a drop does it take to become a red flag? Jeff Zimmerman looks at Mat Latos and other pitchers working with less velocity in 2014.
July 23, 2014
Lonnie Chisenhall's 2014 breakout has been fueled by a significant shift in BABIP. How rare is an increase of that magnitude? Jeff Zimmerman dives into the numbers.
July 9, 2014
Even if Johnny Cueto regresses to the level of his ERA estimators, he'll still be elite, but can he stay healthy in the second half? Jeff Zimmerman looks for hidden value on the mound.
July 2, 2014
Dallas Keuchel doesn't have an elite strikeout rate, but he has parlayed his high groundball rate and infield flyball rate into a breakout campaign in 2014.
June 25, 2014
Is Mookie Betts a good bet to become a productive big league hitter? Jeff Zimmerman breaks down the current crop of hitting prospects to find the players most likely to become productive bats at the top level.
June 18, 2014
Jose Abreu has provided even more power than expected through his first two-plus months in the big leagues. Can he sustain that level of home-run production?
June 11, 2014
Madison Bumgarner had room for improvement with his walk rate entering 2014. Jeff Zimmerman explains the hidden value in pitchers with room to improve their control.
June 4, 2014
Finally healthy again, Johnny Cueto has delivered a huge profit through the first two months of the season. What level can he sustain the rest of the way? Jeff Zimmerman ponders that question.
May 29, 2014
Where has Eric Hosmer's power gone? Jeff Zimmerman breaks down the tape to determine why the home runs have disappeared for the Kansas City first baseman.
May 22, 2014
Where has Domonic Brown's power gone? Jeff Zimmerman takes a look at the early-season indicators that can reveal skills loss.
May 14, 2014
Tim Lincecum's dominant start against the Braves earlier this week has left some to wonder if he's returning to his once-elite form. Jeff Zimmerman breaks down the impact of swing-and-miss lineups on starting pitching performances.
May 8, 2014
Jose Abreu has shown excellent power early on, but is a correction on the horizon? Jeff Zimmerman takes a closer look at early home run and flyball data.
May 1, 2014
While Starlin Castro is rebounding from a dismal 2013 at the plate, he no longer looks like a threat to steal 20 bases. Jeff Zimmerman takes a look around the league at early stolen-base indicators.
April 23, 2014
Should you Buy High on Ervin Santana? Jeff Zimmerman shares his plan of attack for predicting ERA based on other early-season metrics.
April 16, 2014
Few metrics have stabilized to this point in the season, but there is enough data to put the pieces together for expected batting averages. Jeff Zimmerman explains...