Looking at last season's rise of Adam Wainwright, Matt Garza and Ubaldo Jimenez as legitimate top of the rotation starters I decided to look for some common traits these pitchers had and see if I could spot some of next season's possible breakout candidates.
Some could argue that Adam Wainwright's breakout came in '08 after posting an 11-3 record in only 20 starts (his 2008 was cut short by a sprained middle finger on his pitching hand) but significant strides made in his K/9 (going up from 6.2 to 8.2 in one season) along with the consistent command of his above average curveball induced more opposing batters to hit groundballs (rose from 45.9% to a career high 50.7% from '08 to '09) as well as an increase in swings outside the strikezone. Matt Garza was another beneficiary of what can happen when your K/9 goes up almost two clicks (from 6.9 in '08 to 8.5 last season) thereby solidifing his status as a valuable part of Tampa Bay's rotation. Ubaldo Jimenez always had a promising fastball but his high BB rates kept him from being a legitimate MLB option. Wisely, the Rockies knew Jimenez had the arsenal to be a starting pitcher (they could have easily took his 4 seam fastball that can touch 100 mph and threw him in the bullpen hoping he could be an immediate closer). Last season, Jimenez put it all together and the advancements made to his slider and changeup helped to increase his K/9 (from 7.79 to 8.17) and, most importantly, decreased his BB rate (from 4.67 in '08 to 3.5 last season).
Of course other pitchers made considerable leaps from their 2008 to '09 seasons (Zach Grienke, Jon Lester, Josh Johnson and Edwin Jackson come to mind). However, most of these leaps were expected given the status of each of these pitchers going into last season. Below, I have posted three players I expect to breakout after showing some promising traits last season.
Jason Hammel, Colorado Rockies: Early in his career, Hammel had a problem keeping his pitches up and was burned by the HR rather frequently (allowing 30 HR's in 207 IP, which covered three seasons). The decision for the Colorado Rockies to trade for a pitcher so prone to the longball had to make some fans question this strategy in April of 2009.
Last season, Hammel was penciled in as the #5 starter but didn't make his official start until April 27th and ended up pitching in a career high 176 innings. He also made excellent strides in consistently throwing his curveball for strikes as well as maintaining his growing groundball rates which first appeared during his last season with the Tampa Bay Rays in 2008. Hammel did struggle a bit at home last season giving up 12 HR's in 81.2 IP. He was also hounded by some bad luck with a BABIP listed at .337 and a strand rate coming in at a lowish 69.5%.
Both stats do point to Hammel's getting a positive bounceback but to exhibit a bonafide breakout in 2010 Hammel needs to restablish his changeup. He had some limited success with this pitch in 2007 and 2008 but he has been using it less since the '07 season (usage patterns on his changeup are 16.6% in '07; 11.2% in '08; 9.6% last season). It may be a stretch to expect him to suddenly pick this pitch back up and throw it with any above average skill but I believe the positive trends in his BB and K rate still makes him a pitcher to watch in 2010.
Felipe Paulino, Houston Astros: Here's another back of the rotation starter hounded by a lousy BABIP (.368) and low strand rate (67.6%). Anyone who reads quality fantasy baseball analysis shouldn't be too surprised by this selection but here are the facts: last season he posted a K rate of 8.57 and reduced his BB rate to a manageable 3.41 in 97.2 MLB innings pitched. His fastball has a lot of life and averaged at 95 mph in 2009 but he does tend to keep it up when he tires. His best pitch seems to be his low 90's slider but other than that he'll need to work on a third pitch in order to be an effective starter.
There is still a chance Paulino could be moved to the bullpen but the significant improvements made with his curveball in 2007 and '08 being technically a lost year due to a pinched nerve in his shoulder keeping him out of action (surgery was avoided), I think the Astros would be better served to be patient and with his improving command along with a better handling of his curveball he could be a top of the rotation starter if everything goes right.
For more on Paulino, I recommend reading this recent piece by John Sickels...
Clay Buchholz, Boston Red Sox: Since throwing a complete game, no-hitter during his rookie season in 2007, many figured that Buchholz would be established as Boston's ace by now. Since that time his status as a can't-miss-prospect has tarnished a bit as he struggled with his command in '08 (4.86 BB/9 in 76 MLB IP), watched his K's drop last season (from 8.53 in '08 to 6.65 in '09) and has been bit by the long ball in both seasons (1.30 and 1.27 HR/9 in '08 and '09).
Buchholz has been solid during his brief minor league stints over the past three seasons and solid peripheral stats do point to a player possibly putting it all together in 2010. Next season he'll be 25 years old and his rising groundball rates and decreasing linedrive percentages (38.5%/28.8% in '07; 47.7%/20.9% in '08; 53.8%/17.6% last season) should work to alleviate his high HR/FB tendencies (14.7% in '08; 15.7% last season). Buchholz also has a wide variety of pitches and last season established a higher average velocity on his fastball (93.5 mph). He also used his slider with a bit more frequency; however, his 77 mph curveball wasn't used as much in '09, although it did register as a slightly above average pitch according to FanGraphs Pitch Value Chart last season.
Buchholz has always been knocked for his slight frame (since 2007 he has been listed at 6'3" and 190 lbs) but this spring he reported to camp 13 pounds heavier. If Buchholz can command all four of his pitches with consistency (the data supplied by FanGraphs shows no reason to doubt this) then the next hurdle will be for him to put it all together and become, as the cliche goes: a pitcher instead of a thrower.