Towards the end of August of this season, as Jon Lester was wrapping up a month in which he would strike out over four times as many batters as he would walk and hold opposing hitters to a .178/.242/.271 line, I thought it might be interesting to see how he was stacking up from an historic perspective thus far in his young career. Let's leave aside his personal story for the moment and take note of the fact that at the age of 25, he has now posted back to back seasons of better than 140 ERA+ pitching while throwing a good amount of innings and backing it up with impressive peripherals. What's more, his strikeout rate has jumped more than 50% in 2009 over 2008 to nearly 10 strikeouts per nine innings, suggesting he may have developed to the point where he will be an elite pitcher for years to come.
But let's stick to the present. I wanted to have a look at how many other players in the last 50 years had pitched as impressively as Lester had in his 24 year-old and 25 year-old Big League seasons. So of course, I ventured over to Baseball Reference's Play Index. Parameters: Since 1959, the best combined 24-25 seasons, minimum 350 innings pitched, as determined by Adjusted ERA+. Admittedly I cherry-picked these parameters because they apply specifically to what I had observed about Lester - that he had been very good in his 24 and 25 seasons. Here is the list this criteria produced:
Player From-To ERA+ K/9 K/BB Appier '92-'93 173 6.77 2.26 Lincecum '08-'09 170 10.51 3.48 Santana '03-'04 166 10.11 4.30 Greinke '08-'09 155 8.88 4.07 Pedro '96-'97 154 10.36 3.85 Seaver '69-'70 152 7.84 2.98 Clemens '87-'88 148 9.02 3.77 Zito '02-'03 145 6.40 1.98 Oswalt '02-'03 145 7.89 3.47 Webb '03-'04 143 7.78 1.80 McLain '68-'69 143 6.28 3.55 Lester '08-'09 143 8.16 2.91
Yes, it’s arbitrary but take a look at that. We are witnessing three of the best 25 year-old pitchers of the last 50 years. In fairness, Tim Lincecum and Zack Greinke are in a league all their own but Lester holds his own, showing up 12th on the list. And with his peripherals as strong as ever but his balls in play luck down a bit, Cole Hamels, another 25 year-old, probably deserves a spot here as well. Had he posted ERA numbers similar to his 2007 and 2008 seasons in 2009, he would be right there.
What’s even more interesting is that when you take a look at the head scratchers, the guys that might make you inclined not to place much stock in such a list, a look at their peripheral numbers accurately predicts which pitchers would continue their greatness and which pitchers might take a step back. Kevin Appier and Barry Zito, for instance, rank at the bottom of the list in K/9 and K/BB. Soon after their 24-25 seasons, Appier and Zito would both settle in as very good pitchers and not the great ones their ERA figures might have suggested they had become. You could place Brandon Webb in that category, too, but his ridiculous 119 walks in 2004 badly skews his numbers. Never again has he even approached that number of bases on balls. Denny McLain’s K/BB numbers were terrific but his K/9 figure did not quite stack up. Either way, injury and off-the-field trouble would derail McLain’s career.
So we have whittled the list down a bit. We’re going to keep Webb for the reasons specified above but eliminate Appier, Zito and McLain. Also, let’s take the following into account; since the All-Star Break 2008, in 43 starts, Lester has posted a 9.2 K/9 and 3.48 K/BB – numbers that push him a lot closer to that Lincecum and Greinke neighborhood than the Appier one. Like Timmy and Zack, Lester’s future looks bright. With our new list, Lester finds himself alongside the no-brainer 2009 AL and NL Cy Young Award winners, Johan Santana, Pedro Martinez, Tom Seaver, Roger Clemens, Roy Oswalt and Webb. Not bad company at all.
The Play Index is great fun for things like this. If you suspect one of your favorite players might be inching up (or down) into select company, have a look. In this case, I learned that baseball is currently showcasing some of the most promising - historically promising - young pitching talent to burst onto the scene simultaneously in years. And that Jon Lester is one heck of a pitcher.