What's Wrong with Jon Lester?

Over the past two years, Jon Lester has been one of the best pitchers in the game of baseball. In both 2008 and 2009, Lester won at least 15 games while maintaining an ERA under 3.45.

Last year, Lester struck out 9.96 batters every nine innings while allowing just 2.83 walks. His 3.15 FIP (Fielding Independent Pitching, a statistic combining strikeouts, walks and home runs) was better than all but fours pitchers in the American League.

At the young age of 26, Lester is one of the most promising stars of the game.

This year, however, Lester has gotten off to a rough start. In the season opener against the Yankees, the Red Sox ace allowed four runs in just five innings. Another four runs in five innings were given up by Lester in his next start against the Twins. Finally, yesterday, poor Jon Lester gave up seven runs in six innings to the Tampa Bay Rays.

So what's wrong with Jon Lester?

Should Red Sox fans and fantasy owners (such as myself) be worried? The answer is: No, not yet. Despite a 3.79 career ERA, Jon Lester has a 5.46 career ERA in March and April. In fact, last year, Lester carried a 5.65 ERA through May before ending the season with a 3.41 ERA.

Another reason not to fret over Lester's poor start is the tough teams he's faced since the season began. In his first three starts, Lester pitched against the Yankees, Twins and Rays, all of whom have averaged more than five runs per game.

Despite the teams he's pitched played and his habitual slow starts, there is one foreboding change in Lester's pitching: the rate at which he is walking batters.

So far this season, Lester's walk rate has been a horrendous 5.65 walks per nine. In the past two seasons, Jon Lester's walk rate never exceeded 3 walks per nine.

The obvious cause of Lester's high walk rate is that he is throwing outside of the strike zone more than normal.

Throughout his career, Lester has found the strike zone 49 percent of the time. As of yesterday, Lester has thrown just 41.6 percent of his pitches for strikes.

As I was researching Lester's statistics, I came across an interesting observation in the splits. Lester's walk rate of 4.1 against righties is significantly lower than his walk rate of 7.2 against lefties.

I also noticed that Lester's curveball and cutter, two of his most frequently used pitches, have become less effective. The cause of both of these things is that Lester's curves and cutters are landing down and in (for right handed batters) and lefties aren't swinging at them.

In a recent game against Tampa Bay, Lester threw 12 pitches down and in, outside the strike zone against right-handed batters. Six of these pitches were failed hacks resulting in strikes. Meanwhile, Lester threw six down and in pitches against left-handed batters but only two of those were swung at.

Because lefties are more disciplined on Lester's pitches outside of the zone than righties, they ground out and strike out fewer times than righties. Lester's GB/FB ratio against righties is 2.86 while the ratio against lefties is 1.17.

Lester's biggest problem is that he's throwing his pitches outside of the strike zone and hitters aren't biting, lefties especially. Most of Lester's pitches that are leaving the strike zone and not being swung at are curveballs and cutters.

Lester's fastballs are getting pounded on and are a result of him lacking different pitches to effectively throw at hitters.

All in all, I think Lester will return to the level he was playing at last year.

Keep an eye on him in his next few starts. Be sure to see if he's still constantly missing the strike zone. I think that once Lester's control returns and his curveballs and cutters start reaching the strike zone, it will help the rest of Lester's pitches be more effective.

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