There is no doubt about it, Jon Lester has been the ace of the Red Sox staff thus far. He has already thrown 2 complete game shut-outs (1 of them being a no-hitter). Of his 18 starts this season, 11 of them have been quality starts. That means 61% of the time he has gone 6+ innings and allowed 3 runs or less. Compare that to Daisuke Matsuzaka who has 5 quality starts in 14 total games started and there should be no debate about the excellence of Jon Lester.
The true question is whether or not he can keep it up. This can be broken down into two sections, performance and stamina.
Walks have always been Lester’s biggest problem. When you walk hitters, you’re just setting yourself up for failure. Base hits WILL happen and when you’ve got runners on base due to a free pass, they WILL score. Take a look at some statistics from the season so far:
April - 3.79 ERA, 35.2 IP, 20 BB, 18 K May - 2.97 ERA, 36.1 IP, 13 BB, 27 K June - 3.03 ERA, 32.2 IP, 3 BB, 19 K
As his walks decreased, so did his ERA and it’s no surprise that his strikeouts increased because of this drop in free passes. When you have good stuff and you’re hitting your spots, hitters don’t have a choice but to swing. His numbers have gotten better and better throughout the course of the season and as such there is no reason to think his performance will decline.
Jon Lester is only 24 years old; and had to go through extensive chemotherapy not much more than a year ago. He has never pitched more than 150 innings in a year and is already up to 117.2 so far while being on pace for well over 200. Lester also ranks 8th in the entire MLB in PAPs or Pitcher Abuse Points ( link).
There IS some good news though; because he was drafted straight out of high school, the early innings put on his arm were all monitored by Red Sox staff and coaches. This means that his arm wasn’t being used and abused by some college coach for their own personal gain. Every pitch he threw was counted and watched by trained professionals whose main job was to keep Lester healthy and get him to the big leagues. This will definitely help him in the long-run.
It also helps that the statistics I mentioned earlier are a bit misleading. Lester may be on pace for over 200 innings but thanks to the crazy opening to the season, his spring training was cut short and his first start was earlier than expected. The couple of innings he threw against the Athletics in March should be looked at as nothing more than his last spring training start.
The PAP statistic is also not a perfect one. The way it works is they assign a point value for every pitch thrown over 100 pitches. More points for more pitches, makes sense right? The only problem is that there isn’t a way to quantify what kind of pitch was thrown. A pitcher throwing an 85mph slider for his 120th pitch of the game is certainly at more risk than a pitcher throwing a 75mph change-up. The slider is one of the rougher pitches to throw and Lester has abandoned it completely, relying more on his cutter and curveball.
Another thing worth mentioning is that Jon Lester spent the offseason on an arm strengthening program similar to the one Jonathan Papelbon is on. The Red Sox have a LOT of medical professionals on the payroll and for good reason as they seem to do an excellent job keeping their young pitchers healthy. This could have a profound effect on how many innings he is able to throw in 2008.
Unfortunately the bottom line is that there is no way to predict Jon Lester’s stamina for the rest of the season. One option is for the Red Sox to have him skip a start or two so that they can lower his innings down to a more manageable 190. Another is to take him out of blow-out games a bit earlier than normal and let the bullpen finish it off. All I know is that Boston will do whatever it takes to make sure Lester stays healthy this season and for seasons to come.