How Much to Believe in Jon Lester’s 2014

It would appear that, today or tomorrow, Jon Lester will decide where he’s going to pitch, and that move will set a whole lot of others in motion. One way or the other, the Red Sox will gain some clarity. The Cubs will gain some clarity, and the Giants will gain some clarity, and other teams unrelated to the pursuit will also gain some clarity. Lester will cause an already active market to accelerate, and what’s interesting about that is that Lester isn’t even the best pitcher available. Unless he is, which, well, let’s get into this.

Last year, Lester and Max Scherzer was basically even. Lester was perhaps even a little better, but when you factor in the uncertainty that’s always there, both of them were right around six-win pitchers. That tells you one thing. Looking at a longer track record tells you another thing. Over a three-year period, Scherzer’s been superior. The margin’s not even that close. This is one of the reasons Phillies fans believe that Cole Hamels has significant trade value — they don’t see him as being worse than Lester. Last year was an important one for Jon Lester, and the result is he’s going to earn a lot more money than he would’ve otherwise, but the big pressing question is, how much did last year mean, relative to the previous years?

Lester had pitched like an ace before. That was a while ago. After pitching like a 5-6 win pitcher, he dropped to the 3-4 win level. That spanned 2011 – 2013, and then came 2014, when Lester had himself a contract year for the ages. Between the last two seasons, Lester improved his K-BB% by 7.2 percentage points. Over the last 40 years, 1,378 starting pitchers have thrown at least 100 innings in back-to-back seasons, where in the second season they were at least 30 years old. When you rank them by K-BB% improvement, Lester shows up in the top 2%. What he did wasn’t unprecedented, but what he did wasn’t common.

So, you look at what he did and break it down. It’s neat when it works out this way:

Season	xFIP, righties	xFIP, lefties
2011	3.84	3.02
2012	3.92	3.54
2013	4.11	3.15
2014	3.04	3.30

You’re always trying to isolate changes or improvements. Lester didn’t get any better against lefties. He was already good against lefties. The difference was that Lester got a lot better against righties, which, of course, represent the majority of his plate appearances. To give you an even better idea:

Season	K-BB%, righties
2011	12.2%
2012	9.8%
2013	9.9%
2014	19.3%

This isn’t necessarily a great shock. We know that, overall, last year Lester got better. So that improvements would have to show up somewhere in the splits, and it happens to show up in his performance against right-handed hitters. Where this gets really interesting is when you examine what Lester was doing, compared to what he used to do.

Here now are some Jon Lester heat maps, for pitch location. This is against righties only, over each of the last four years:

In some ways it’s even more extreme than it looks. Last season, Lester abruptly changed his pitching approach against righties, repeatedly pounding hitters inside.

There are two possible directions. Lester threw inside a lot more often. He also threw fewer changeups, all but eliminating the pitch and compensating by throwing more cutters and curves. So he either threw inside more because he got rid of the changeup, or he got rid of the changeup because he wanted to throw inside more and the changeup is mostly supposed to stay down and away. Whatever the case, a change was made, as Lester attacked in more than almost anyone else.

Here are percentile rankings for Lester among left-handed pitchers, in terms of throwing inside to righties:

• 2011: 50th percentile
• 2012: 52nd
• 2013: 76th
• 2014: 91st

Last season, Lester was in the 91st percentile in throwing inside against righties, and he was in the bottom two percent in throwing over the middle of the plate against righties. Lester’s never been one to leave too many pitches against righties over the middle, but last year saw him be particularly extreme. If you don’t care for percentiles, here are raw frequencies, showing Lester’s rate of pitches to righties over the inner third of the plate or beyond:

• 2011: 36%
• 2012: 36%
• 2013: 39%
• 2014: 49%

This just takes you back to the heat-map .gif. It used to be that Lester would throw an awful lot of pitches around the outer edge. He by no means stopped doing that, and that’s where he picked himself up a lot of called strikeouts, but Lester became more of a two-edge pitcher, using fastballs and cutters side-to-side and then throwing in the occasional breaking ball down out of the zone. The change in approach implies a change in strengths, and a change in strengths implies a change in ability. Though Lester got some attention for an improving changeup in 2013, he almost ditched it last summer, and his performance only shot up.

So we wonder. We know there exist performance spikes. We know that, with many performances spikes, they’re mostly just noise. We’re always on the lookout for things that can’t just be explained as noise. With any change in performance, there’s going to be some kind of changes you can find underneath. Little things add up to mean big things. But, what do we make of what Lester just did? For example, Zach Duke signed a three-year contract. Many of you might’ve forgotten that Zach Duke was still in the major leagues. He just had a breakthrough performance out of the bullpen, and it seems like the White Sox are comfortable ignoring Duke’s track record, because prior to last year he changed his pitching delivery, so who cares about the past? The past happened with the old mechanics. With the new ones, Duke was awesome.

Lester didn’t overhaul his mechanics in the way that Duke did. In the way that, on the hitting side, J.D. Martinez did. So in that way, Jon Lester still pitched like Jon Lester. But then, he did absolutely pitch differently, and by that I don’t just mean he pitched better. He attacked right-handed batters differently, in a way he hadn’t done before, and that’s not noise. An approach isn’t noise. An approach is a plan, which is the very opposite of noise.

So you figure the approach will stick, as long as Lester keeps having the same weapons. So based on that, how heavily should we weight Lester’s 2014, relative to his previous years? Does he deserve an ordinary projection, or should we be more inclined to downplay the history, since he made legitimate adjustments? The cop-out answer is that we should compromise. Kind of split the middle. Ultimately, Lester had an extreme performance, and extreme performances should be expected to regress. But, consider what Andrew Miller just signed for. That only happened because Miller took a step forward in 2014, which the Yankees elected to believe in. Lester’s 2014 was pretty damn convincing.

It’s because of Lester’s 2014 you might be able to say he’ll sign a massive contract with upside. Scherzer will get paid for being Scherzer, and we have a good idea of how great he is. Lester will get paid like a guy with just a few question marks, yet he’s demonstrated the ability to pitch like an unquestioned No. 1. Maybe, the signing team will be the team that most heavily weights Lester’s 2014. Yet his history won’t count for 0%, and then that’s where the upside is. It’s only a very small factor, but with contracts this big, there’s almost never any upside to speak of. In that regard, Lester’s a special case.