Blue Jays by the numbers: A closer look at Brett Cecil's struggles

By reputation and past results, Brett Cecil is supposed to be the rock of the Toronto Blue Jays' bullpen.

But while Toronto's relievers have mostly settled in as the season nears its midpoint, Cecil is struggling to do his part recently. His latest meltdown came Sunday when he allowed four runs in the top of the ninth with the game tied at 9-9 and the Blue Jays lost to Baltimore 13-9. The left-hander has given up runs in five of his last six outings.

"I’m just battling right now,” Cecil told reporters following Sunday's loss. "I don’t have a real good answer for (what happened). I’m just battling."

Since becoming a full-time reliever in 2013 after spending the better parts of four seasons in the rotation, Cecil established himself just a tier below baseball's elite late-inning hurlers. Over those two years he put up a 2.76 ERA and was worth two wins above replacement according to FanGraphs. This season though Cecil's ERA is 5.96 despite no drastic changes in his strikeout, walks, and batted ball rates.

One explanation for the increased ERA is that Cecil's HR/9 has jumped to 1.59, but there has to be more to it than that because two of the four home runs he's allowed were in one game in mid-April.

Cecil's repertoire as a relief pitcher is quite different than what he threw as a starter. His spike curveball, the pitch he used fifth-most while in the rotation, has become his go-to out pitch to great success. He's thrown the curve over 37% of the time out of the bullpen and this season has generated a swing-and-miss on that pitch 25% of the time, which ranks among the best whiff rates in the league.

So if his curveball is still hugely effective, what's the problem?

According to the PITCHf/x data collected by Brooks Baseball, Cecil hasn't been able to command his pitches like he did in 2013 and 2014. The fastball stats in the table below include four-seam fastballs, cutters, and sinkers.

The lack of fastball command is what's most alarming, even if he's not necessarily walking more batters. It's not just that failing to throw strikes makes his offspeed pitches less dangerous, but the pitches he's throwing in the zone are getting crushed. Opposing hitters have a .421 batting average and are slugging .632 on Cecil's fastballs over the plate. These are the slim margins relievers live and die by.

The Blue Jays have serious decisions to make before the July 31 trade deadline. There will be calls for the front office to go out and improve the starting staff and the bullpen. Whether or not Cecil can shake off these struggles soon is going to impact which of those two Toronto decides to prioritize as the more important need.

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Israel Fehr is a writer for Yahoo Canada Sports. Email him at israelfehr@yahoo.ca or follow him on Twitter. Follow @israelfehr