Sometimes a pitcher just has a bad year and sometimes he's also unlucky. I identified two pitchers from last year who may fit that description based off of advance metrics. 

Let's start with Martin Perez, who last year, pitching for the Minnesota Twins - put up a 5.1 ERA. Not good, right? Well, dive a little deeper. Perez had the biggest gap among all starting pitchers between the batting average against him and what's called expected batting average. That's a number based on how hard balls were hit off of Perez. He also right number three among all starting pitchers in the gap between slugging percentage allowed and expected slugging percentage. Number one in that category?

 That was Yusei Kikuchi of the Seattle Mariners, who pitched to a 5.46 ERA And clearly pitched better than that. Now Perez is 29. He just signed a one-year, $6.5 million contract with the Boston Red Sox. Kikuchi is only 28 years old. Both have been durable. 

Both pitched better last year than the overall numbers indicated, and both could be in for bounce-back seasons.

Analysis from Max Goodman of InsideThePinstripes: The Yankees should be licking their chops at the opportunity to face Martin Perez in a Red Sox uniform. Perez has struggled in five career starts against New York, posting a 9.97 ERA while Yankees hitters are batting .398 against him with a 1.137 OPS. Those are Perez's worst splits against any other American League team in his career. Sure, it's a small sample size (of just 21 2/3 innings) but Perez fits into the mold of hurlers that New York's high-powered lineup has the tendency to dominate. For a southpaw that relies on keeping the ball on the ground, sluggers Aaron Judge, Gary Sánchez, Giancarlo Stanton and Gleyber Torres—all right-handed hitters with pop—are poised to tee off.