The problem with projecting Jon Lester is that there are two Jon Lesters. From 2008-2011 he averaged an ERA- around 75. He was a full 25 percent better than the league average pitcher, another step or two better than the average starter. He consistently threw 200 innings every year. I looked for similar pitcher peaks on the (fabulous) Baseball-Reference Play Index, and the most useful modern analogue I found is Matt Cain. In April 2012, Cain signed an extension with the Giants worth $127M over six seasons, while he was coming off a run pretty similar to Lester’s peak. There have been two seasons of salary inflation since, but that gives us a good rough estimate of what it would cost to sign peak Lester.
Of course, this isn’t peak Lester. In 2012 Lester was just plain poor. And as I showed over the offseason, Jon Lester’s 2013 came in somewhere between his 2008-2011 peak and his 2012 disaster. One thing I’ve read around the internet is that we can chalk up 2012 to the malign influence of Bobby Valentine, and we should ignore that awful season in our projections. The problem with this argument is that we’ve already seen something of a natural experiment. Lester’s ERA- in 2013 was about 90, well above the 75 he averaged at his peak. If you include his excellent postseason, the ERA- drops to about 84. Very good, but still notably worse than Lester did at his best. 2013 tested the hypothesis that Jon Lester’s bad 2012 was a meaningless fluke, and it was found wanting.
So what is a somewhat diminished Jon Lester worth? My quick salary calculator estimates that in the current climate, peak Lester would be worth a contract in the range of 6/150. Based just on his ZiPS and Steamer preseason projections of roughly 3.5 wins above replacement, Lester would project to contract around four years, $70M. The Red Sox, then, offered Lester a contract which treats Lester as precisely the pitcher his statistics say he is. They did not treat Lester as the pitcher he was three years ago, and they did not ignore his bad numbers from 2012. This contract offer was quickly rejected. Unsurprisingly, Jon Lester himself thinks that Jon Lester is much better than that.
If the Red Sox ace goes out and pitches like the Red Sox ace this season, it’s going to take a lot more than 4/75 to get him signed. That was the risk that Ben Cherington took in keeping the contract offer so low. He chose not to take tha risk of Lester being roughly the pitcher he projects to be. I have been impressed with how Lester has pitched in his first three outings of the season, but it’s hard for me to reject the statistical baseline right now. I hope Lester is great this year and the Red Sox end up having to spend a whole ton of money to keep him. But that’s just hope, and I don’t think the Red Sox were wrong, at this point, to make their contract offer based on hard numbers instead.