Perez was previously a member of the Rangers' rotation for much of his career, but he was dreadful in that capacity the past two seasons, accruing a 5.37 ERA, 1.63 WHIP and 5.5 K/9 across 47 starts. However, last season's 6.22 ERA is a bit of an outlier in the context of the rest of his career, and an elbow injury is at least partly to blame. After inking Perez to a one-year, $3.5 million deal this winter, the Twins probably won't hesitate to move the lefty to the bullpen if he struggles in spring training or early on during the season, but he'll at least get the chance to battle for a back-end rotation gig right away.

Perez gobbled 185 innings in 2017 and 197 frames in 2016. Last year, Texas gave him 5.19 runs of support per start -- the league's 11th-highest average -- and that powered him to 13 wins. He was also helped by another year of velocity gains following 2014 Tommy John surgery. The left-hander may not have the same chance to help the rotation early in 2018, as he underwent surgery in December to repair a fracture in the radial head of his right elbow. Though it's his non-throwing arm, the Rangers still expect him to start the season on the disabled list. Perez has failed to post a K/9 above 5.6 in his last three seasons, and he hasn't even balanced that with a better walk rate than 2.8 BB/9. A contact-dependent pitcher pitching home games at hitter-friendly Globe Life Park deserves plenty of skepticism. It'll take substantial skill development or a favorable change of scenery to excite fantasy owners.

The southpaw has failed to justify his once lofty prospect status. Perez's 3.62 ERA from 2013 looks like a fluke, considering he's suffered with a 4.93 ERA since. To be fair, he's been recovering from 2014 Tommy John surgery, so he deserves some patience, especially with a few encouraging signs from 2016. Per PITCHf/x, his four-seamer (92.9 mph) and two-seamer (92.5) sat at three-year highs. Perez again enjoyed a groundball rate over 50 percent, a skill that can lead to bigger things for the impending 26-year-old. One of his best assets is his ability to land an 0-1 count: His 64.6 first-strike percentage tied for 11th among qualified pitchers in 2016. Plus, Texas' offense helped him reach 10 wins despite his rough performances. Even with all these hidden positives, he must show he can grow beyond pitching to contact. Spring training may offer hints that he could be more than just an innings eater in AL-only leagues. While he carries some post-hype intrigue, it is important to proceed with caution.

Perez wasn't the same guy we saw in a strong 20-start rookie campaign back in 2013, but elements in his return from Tommy John surgery were impressive despite underwhelming results. His groundball rate reached elite levels at 60 percent, and his 65 percent first-pitch strike rate was 21st among 157 starters with at least 70 IP. His velocity returned to his 2014 level, but it's probably wiser to judge him against him pre-2014 levels since he likely pitched some, if not many, of his 51 IP at less than 100 percent leading up to the surgery. In that case, he's a tick behind, though he did close the season with his best marks (93.5 mph in his final three starts including the postseason). It's great that he can generate a groundball with all four of his pitches, but he's at the mercy of his defense and plain ol' luck with this much contact allowed. The skills and multiple injuries conjure thoughts of Brett Anderson; bid accordingly.

Perez was off to a brilliant start in 2014 with a 1.42 ERA in his first five starts, including back-to-back shutouts in mid-April, before finally catching the Tommy John surgery plague that infected the league. The elbow no doubt was affecting him in what would be his final three starts of 2014, when he allowed 19 earned runs in 13 innings on the heels of those shutouts. He allowed 24 hits and walked 10 batters in those three outings after giving up just 26 hits and nine walks in his first 38 innings. While Tommy John surgery is far from a career death sentence and often doesn’t degrade the pitcher at all once he’s fully recovered, it’s not guaranteed he returns to being the pitcher he was. As such, tread cautiously when re-investing in the once-promising lefty. At 24 years old, there is plenty of time for him to rebound, but 2015 is unlikely to offer much for fantasy gamers. He won’t even be considered for a return until midseason and that is a best-case scenario. Wait for 2016.

Perez's season got off to a slow start after he took a comebacker off his wrist late in the spring that kept him sidelined until early May. He was up in the major league rotation for good in late June after a solid string of starts at Triple-A Round Rock. He made 20 starts for Texas, allowing 129 hits and 37 walks in 124.1 innings, fanning 84. Those aren't great peripherals, though his numbers improved as the season wore on. The Rangers believe in the improvement, inking him to a four-year contract that also contains club options for an additional three years. It's hard to entirely dismiss his terrible 2012 season at Triple-A when looking to the future, but he'll have a spot at the back of the Texas rotation for the entirety of the 2014 season.

After a few years of showing the occasional flash of greatness, Perez fell apart in 2012: a poor 69:56 K:BB rate in 127 innings at Triple-A Round Rock, and an accompanying promotion/change-of-scenery to the majors saw much the same (25:15 K:BB in 38 innings). He'll still be just 22 years old when the season begins, but you have to go back all the way to the first half of 2009 (at High-A no less) to see a prolonged stretch where Perez put everything together. He's tradeable now in the right deal, and that wasn't the case 12 months ago.

Perez entered the 2010 season as one of the top young pitching prospects in all of baseball, though an inconsistent season as a 19-year old with Double-A Frisco took some of the shine off his start as 2011 neared. He pitched better last season, though his composite line across two levels (including 10 starts at Triple-A Round Rock) isn't jaw-dropping: 137.1 innings, 152 hits, 120:56 K:BB. The 72 hits allowed in 49 innings at Triple-A is the real warning sign, given that he allowed 117 hits in 99.2 innings at Double-A Frisco in 2010. There's clear bat-missing ability here by looking at his K/9IP totals which remain excellent for such a young starter, but consistency remains a real problem for him right now. Derek Holland struggled with consistency early in his career too, but appears to have turned the corner, so there's still every reason to think Perez projects as a solid No. 2 starter down the road. It's easy to forget he'll still be just 21 years old as 2012 opens.

Perez pitched the full season at Double-A Frisco as a 19-year-old and suffered with his consistency all season. Buried amongst the disappointing campaign was 101 strikeouts in 99.2 innings, but also a whopping 117 hits allowed and 50 walks. His winter ball season was more of the same, mixing solid results with poor ones. He'll likely begin the year back at Double-A Frisco again given his struggles there, and remains among baseball's best pitching prospects given his age and past performance, but a quick start to the season would alleviate some of the worry following a disappointing season.

You don’t see many 18-year-old pitchers skip High-A completely, but Perez did just that when he earned a promotion directly to Double-A Frisco after a solid start to the season at Low-A. He got beat around a bit at Double-A, but was a full year younger than anyone else in the league and we're dealing with an elite prospect here if he can stay healthy. He's the Rangers' best pitching prospect now that Neftali Feliz and Derek Holland have graduated, and a healthy season at Double-A Frisco will place him near the top of the list in all the minors if he's not there already.

Perez made his pro debut as a 17-year old in 2007 in the Northwest League and acquitted himself quite well. Although his component ratios were not outstanding statistically, he held his own considering his age, and scouts like his stuff: 89-93 mph fastball and a nasty-ass curveball. Perez is a long way from the majors, and a lot of questions need to be addressed: can he stay healthy? Can he sharpen his command? Can he develop a changeup? Perez has a bright future if he can keep his arm attached. (Outlook courtesy of The Baseball Prospect Book 2008 by John Sickels, available only at Johnsickels.net.)