Chicago Cubs veteran starter Jon Lester leads Major League Baseball with a 1.16 ERA, which was aided by his start on Sunday where he pitched 6.2 innings and didn't surrender a single earned run against a vaunted Milwaukee Brewers lineup.
While on paper the numbers look phenomenal, and they are, some underlying metrics suggest Lester could be due for some regression.
Jon Lester now has enough innings to qualify.— Cubs Insider (@realcubsinsider) May 13, 2019
Jon Lester is currently MLB’s ERA leader at 1.16. pic.twitter.com/Z3FQh8KjBX
While ERA is a solid statistic, it isn't always the best representation of talent. While Lester's 1.16 ERA is fantastic, it may be a product of some good luck for the 35-year-old.
When you look at Lester's xwOBA (Expected Weighted On-base Average) which takes into account his opponent's batted ball profile, he ranks 51st among National League starting pitchers. That means Lester is getting incredibly fortunate, as while he isn't necessarily negating hard contact, he has avoided surrendering runs.
I'm not sure there is going to be a better $100M+ deal in history than the Cubs signing Lester. He's paid off and then some.— Mike Petriello (@mike_petriello) May 13, 2019
Interesting 2019, though. 1.16 ERA is incredible, yet also 51st in NL SP xwOBA (min 100 PA).
Maybe looking at Lester's xwOBA is digging into the weeds too much, but this statistic is more indicative of a player's skill than some of the more traditional numbers, as it removes defense from the equation, focusing instead on quality contact.
There's no doubt that Lester is Chicago's No. 1 starter, especially given the woes of Yu Darvish, and he'll continue to be the team's ace throughout the 2019 season.
While he's dominated early on, the underlying metrics suggest his success has a good deal to do with luck. Hopefully he doesn't regress too much throughout the rest of the campaign, but it's hard to imagine him keeping up this outstanding pace.