Young Tampa pitching
The 24-year-old Hammel made a bad impression on fantasy owners last year by going 0-6 with a 7.77 ERA and a 1.86 WHIP over nine starts with the Devil Rays. However, he's rediscovered his groove this season in Durham. Hammel has a 2.85 ERA and 1.04 WHIP with 61 strikeouts and 22 walks in 66 1/3 innings. He's also given up just two homers, which is five fewer than he allowed in his nine games in the majors last year. Hammel probably will never be better than a No. 3 starter in the majors, but last year was not a true indication of his ability.
A first-round draft pick in 2004, the 6-foot-9 Niemann had only 108 minor league innings under his belt coming into the season, mainly because of elbow, shoulder and groin injuries. Things have started to come together for the 24-year-old this year, as he's averaging better than a strikeout per inning for Durham. However, as a fly-ball pitcher, he's inherently susceptible to the long ball, so his margin for error isn't as large as it is for others. His walk rate (3.4 BB/9) isn't terrible, but he needs to improve his control or he'll be prone to big innings in the majors. Niemann has greatest upside of any of these pitchers, but he may also have the most work to do in order to reach it.
Rated by Baseball America as just the No. 17 prospect in the Tampa Bay system coming into the season, the 24-year-old Sonnanstine has been the best pitcher in the Durham rotation this season. Over 65 innings, he's posted a 2.35 ERA and 0.97 WHIP with 65 strikeouts and only 13 walks. Like Niemann, Sonnanstine is a fly-ball pitcher, but he limits the damage of the home runs he allows by not walking many batters. In fact, over the last three seasons, Sonnanstine has made 66 starts and walked only 65 batters. Based on the quality of his stuff, he won't be a strikeout artist in the majors, but he has a chance to be a Jon Garland-caliber pitcher.
Acquired from the Royals in the Joey Gathright deal last season, Howell pitched well for Durham after the trade but struggled with the Devil Rays, posting a 5.10 ERA and a 1.56 WHIP in eight starts. The lefty got off to a rough start with Durham this year, but in the month of May he's struck out 42 and walked only six while posting a 3.08 ERA. Plus, despite his overall struggles in the majors, Howell has already proved that his stuff is good enough to induce strikeouts at the big league level (6.8 K/9 over 115 major leage innings). As the only left-hander among this group, Howell might have an edge when it comes time for management to decide who to call up.
Those are your candidates, assuming the Rays don't do something foolish like throw Tim Corcoran into the rotation. Of the quartet at Durham, Howell is best-equipped for immediate success in the big leagues, but none of these guys is likely to post an ERA under 4.00 any time soon. Howell, Hammel and perhaps Sonnanstine would make good low-cost pickups in deep AL-only leagues as soon as they are called up. Niemann is probably last in line for a promotion, but he's the most talented of the bunch, so keep an eye on him in case he strings together several dominant starts in a row.