Arian Foster, RB, HOU - No one's value jumped more over the weekend. Not only did Steve Slaton's fumbling problem recur when he lost one at the goal line Saturday, but the Texans also lost rookie Ben Tate to a season-ending ankle injury. Foster, who has already had an impressive offseason that earned high praise from the coaching staff, is currently locked in as the team's lead back. Slaton remains talented, but he's going to be used in more of a third-down type role it appears, and that's assuming he stops fumbling. Foster gained 31 yards on four carries during his preseason debut, and he's a lead back who can catch passes and should be the goal-line guy in a terrific offense. Consider him a top-20 fantasy back.
Ryan Mathews, RB, SD - We all knew Mathews was in a good situation in San Diego, but with any rookie, there's uncertainty as to whether he can take advantage of his favorable circumstances. While limited action in one preseason game doesn't answer that question, Mathews passed the eye test with an impressive performance against the Bears on Saturday, totaling 61 yards on 11 touches. He exhibited good speed and tackle-breaking ability, and if he turns out to be a stud, huge numbers should follow in Norv Turner's system with an elite quarterback on his side. It's not all good news, however, as Mathews was removed from the game in favor of Mike Tolbert when the Chargers were at the goal line. Nevertheless, Mathews looks like a worthy top-10 pick in fantasy leagues.
Johnny Knox, WR, CHI - Jay Cutler attempted just two passes during his preseason debut, and both were completions to Knox, good for 47 yards. Again, sample-size caveats apply, and Devin Aromashodu gained 78 yards and a score later on, but all indications point to Knox being Chicago's No. 1 wide receiver in 2010. Of course, Mike Martz's offenses tend to spread the ball around, but Knox appears to be an ideal fit, and his rapport with Cutler is apparent. Knox missed practice Monday with an injury, but it's supposedly minor. In a Martz led offense with Cutler at the helm (and a fading defense that will have to deal with a bunch of turnovers on offense), would it surprise if Cutler throws for more than 4,500 yards? You'll want the team's No. 1 wide receiver on your fantasy squad if that happens. Even though Knox is no longer a sleeper, I'd argue there still isn't a bigger bargain going in the middle rounds.
Brian Westbrook, RB, SF - There's only a backup role available with Frank Gore around, but Westbrook liked the situation in San Francisco, especially after Glen Coffee abruptly retired, so he signed with the 49ers on Monday. Rookie Anthony Dixon totaled 125 yards on 24 touches against the Colts on Sunday, showing good strength and an ability to break tackles in the process. Still, coach Mike Singletary hasn't been overly impressed with the raw Dixon, and Westbrook is obviously far superior in pass protection. At age 31, Westbrook is a huge long shot to remain healthy, but with just 1,308 career rushing attempts, he can remain productive when on the field (he averaged 4.5 YPC last season), making him San Francisco's new obvious RB2.
Eddie Royal, WR, DEN - Royal was one of the biggest fantasy busts last season, as he wasn't just bad, he was truly awful, somehow managing just 345 receiving yards with zero touchdown receptions despite staying relatively healthy. As a result, he should be an afterthought in many drafts in 2010, but there are worse late round fliers. Kyle Orton has a firmer grasp of Josh McDaniels' offense, and Brandon Marshall has been shipped to Miami, leaving a huge void in the Broncos' receiver rotation. Jabar Gaffney is probably the first WR to target in Denver, but Royal looks likely to play in the slot, his most natural position where the Broncos refused to utilize him last season. Demaryius Thomas no doubt has the most talent of all Broncos' receivers, but he's recovering from foot surgery and is a rookie coming out of a gimmicky college system. The Broncos figure to throw quite a bit with a poor defense, and their schedule is favorable.
Michael Vick, QB, PHI - Vick completed 11-of-17 passes for 119 yards during the Eagles' win over the Jaguars on Friday. While he also threw a pick and posted a 60.7 QB rating, the real news is how he looked athletically, rushing for 50 yards and a touchdown on six carries. It took a year back in football, but it certainly appears Vick's explosion has returned. With Donovan McNabb out of town, he's also moved up the depth chart, so he's just one injury away from taking over the keys to a highly productive offense. For all of Vick's faults, both on and off the field, his rushing ability always made him quite an enticing fantasy property. He's back on the radar.
Dez Bryant, WR, DAL - Bryant had his protective boot removed Friday and did some light running Saturday, which is great news for someone who suffered a high ankle sprain just two weeks ago. Dallas might remain cautious and still hold him out of all preseason games, but it sure appears like the explosive rookie should be ready for Week 1. He's going to be behind the curve of an already tough position to learn after missing so much practice time, but eventually he should become an integral part of a terrific offense with an elite quarterback throwing to him. Bryant will remain behind Miles Austin as Tony Romo's preferred target, but once he's up to full speed, he should have little trouble surpassing Roy Williams on the depth chart. Bryant is a special talent.
Larry Fitzgerald, WR, ARI - Fitzgerald left Saturday's game with a knee injury. An MRI later revealed only a minor MCL sprain, and he's expected to be ready by Week 1, but it's a bit worrisome moving forward regardless. The injury is enough to bump him below other receivers like Calvin Johnson and Miles Austin on your cheatsheets.
Chad Ochocinco, WR, CIN - For the second straight game, Ochocinco took a backseat to Terrell Owens, recording just one catch for four yards while Owens was targeted repeatedly. Of course, it's just two preseason games, and it's possible Carson Palmer is just trying to appease his new teammate. Even so, Owens' presence really hurts Ochocinco's value, which was already tenuous in a run first offense with a QB who now lacks arm strength throwing to him. It's becoming a stretch to consider Ochocinco a top-20 fantasy wide receiver right now.
Fred Jackson, RB, BUF - Jackson will be out four to six weeks with a broken bone in his left hand, leaving his status for Week 1 up in the air. Jackson, who graded out as the single worst blocking back in football last season, already had a shaky hold on Buffalo's RB1 role. C.J. Spiller may not be a workhorse, but he's clearly the most talented running back on the Bills' roster, and Marshawn Lynch looms as well. Jackson's fantasy stock is falling fast.
Visanthe Shiancoe, TE, MIN - First off, Shiancoe's value would plummet if Brett Favre didn't return. While Favre is likely to come back, there's still reason to view Shiancoe as overvalued right now. There's no doubt he's a strong red-zone threat, but with such modest targets (he saw 79 last season), another 11 touchdowns like he scored last year seem unlikely. And since Shiancoe averaged just 35.4 yards per game in 2009, his value is entirely tied to scoring. The fact his current ADP (TE9) is ahead of Zach Miller's is borderline insane.
St. Louis Wide Receivers - Sam Bradford has impressed, and there will almost certainly be one Rams' WR who is worth using in fantasy leagues this year. The problem is identifying which one, both during your draft and quite possibly on a weekly basis as well. Donnie Avery enters as the favorite to act as the WR1, but he's proven to be a huge injury risk. Others are high on Laurent Robinson, but Brandon Gibson showed good ability after coming over in a trade with the Eagles midseason last year. And then there's rookie Mardy Gilyard, whom the team took in the fourth round and for whom it has high hopes. It's quite the crapshoot.
Derrick Ward, RB, TB - As the backup for a team that's improving with the brittle Carnell Williams in front of him, Ward actually looked like a sleeper at one point. But after gaining a paltry 20 yards on 12 carries (1.7 YPC) and also losing a fumble during the Bucs' loss against the Dolphins on Saturday (he blamed it on the field conditions, which were admittedly awful), his roster spot may very well be in jeopardy, as Kareem Huggins has really impressed. Ward's exorbitant contract makes him a truly viable option to be released.