During 2011 and 2012, Vinnie Pestano was one of those stud relievers who flew under the radar because he did not have the “closer” tag. Some probably noticed him, as he averaged almost 11 strikeouts per nine innings during those seasons, a 2.45 ERA, and did a nice job keeping the ball in the park. Some probably wondered if Pestano, rather than Chris Perez, should have been Cleveland’s closer.

Currently, Pestano is getting something of a shot with Perez on the disabled list for the last few weeks. Given that Perez is not exactly lighting it up in his AA rehab assignment (well, at least not lighting it up on the mound), Pestano may be needed in higher-leverage situations for a while longer. In the past, Pestano might have seemed a great candidate for that, but he is struggling this season. His 4.05 2013 ERA is not great for a reliever to begin with, but more troubling is his 5.30 FIP. Pestano has only had 20 innings of work, and we all know the mantras of reliever volatility, but there are some troubling indicators here.

As one can see from Pestano’s FIP, it is not as if he has been subject to the usual “luck” problems one often sees with pitchers. His BABIP his year is .269 (right in line with his career numbers), and he has stranded runners at an above-average rate. From looking just at those numbers, if anything, Pestano has been “lucky” this year. Given that his ERA has been poor for a reliever, especially a high-leverage reliever, that is a bad sign.

Pestano’s strikeout rate is down this year from both 2011 and 2012, and although that is an issue, it is not the only, or even primary problem. Just looking at the components of FIP, the main problems are increased walks and home runs. Pestano has never been a control pitcher, but with his strikeout rate high in past seasons, a walk rate just under 10 percent was fine. However, at the the same time his strikeout rate has dropped, Pestano’s walk rate is up to 11.5 percent. He is not only allowing more balls in play (and his contact rate actually jumped already in 2012), but is putting more runners on with the free pass — not a good combination.

Perhaps even more dramatic has been Pestano’s increase in home run rate. While home runs per nine innings is not the best denominator, it does nicely highlight what has happened with Pestano. In 2012, his home runs allowed per nine innings was .90, this season so far it is 1.80, double the rate. Part of this is that 14.3 percent of Pestano’s fly balls allowed have gone out of the park. Of course, home runs per fly ball is subject to about as much random variation for pitchers as one can imagine for both relievers and starters, so in itself it is not a concern.

A bigger issue is that Pestano is allowing a greater proportion of balls to be hit in the air than in past seasons. After hanging around 40 percent in previous seasons, his ground ball rate is down to around 27 percent this year, and his gly ball rate has jumped from about 42 percent to 50 percent. The more balls that are hit into the air, the more balls that have a chance to go out of the park. Combined with more frequent contact and putting runners on more often, even with a regressed home run per fly ball rate, things look ugly, hence Pestano’s 4.67 xFIP on the season.

All of this is in a small sample for the season. But it is worth remembering that for pitchers, observed ground and fly balls rates become relevant to true talent relatively quickly, and walk, strikeout, and contact rates follow relatively closely. All of these have been issues for Pestano this year. This is not to say that there is no random variation at work with Pestano’s performance in these rates this year. But this is not just a case of the bad BABIPs or something like that.

Pestano did have some injury problems this year, spending some time on the disabled list in May due to elbow inflammation. His overall fastball velocity in 2013 has been a bit down from 2012, although he had a bigger drop from 2011 to 2012 without the rest of his problems. Just looking at 2013, one sees that his fastball velocity was down to about 90 miles per hour in May, while being almost 93 in April and almost 92 so far in June. I try to stay away from specific injury analysis (or linking it to “WBC hangover”), but I do not think it is going too far to say that dealing with the injury and the recovery might have had something to do with Pestano’s problems this year. One should not be too hasty with this — it is not as if Pestano has been good other than May, and his velocity was actually high in April before he went on the DL near the beginning of May, so simply reasoning from the DL stint does not explain everything away.

Treading on even thinner sample-size ice, if we look at Pestano’s month-by-month performance, May stands out, and, to a lesser extent, April. The main problem was not strikeouts (about the same rate as before and after). His percentage of batters walks, 12.5 percent, was the same in both May and April, so it may be that the elbow had been giving him trouble with his control even beforehand. What stands out, again, is his fly ball rate. Pestano really had trouble with home runs in May, combining a 62.5 percent fly ball rate combined with a 20 percent home run per fly ball rate. If the elbow was giving him problems putting the ball where he wanted it, it may already have been an issue in April, when he was giving up a still-high 55 percent fly ball rate while (perhaps) being more fortunate with respect to home runs on those fly balls (9.1 percent).

If the season thus far for a reliever like Pestano is a small sample, then month-by-month splits are even more ridiculously small. We do seem to have reasonable cause for his struggles with walks and fly balls — both rates were poor in April and May, and in June seem to be on the way to resolving themselves. But even that may not be reassuring. For one thing, as noted above Pestano’s velocity was highest in April (again, I am not sure exactly if “WBC hangover” is supposed to work on a delay or not). For another, he actually missed most of the first half of May with his injury. His May numbers come from after he returned from the disabled list. And his velocity was at its lowest at the end of May.

It would be overly speculative and simplistic to assume that this means the disabled list stint did not do anything for Pestano. His fastball velocity has been back up since the end of May, although it is not yet to the levels of April. It might have taken Pestano some time to get back where he wanted to be. He has done a better job of keeping the ball on the ground, and of not putting runners on with walks in June, which is a good sign. Still, a 4.63 FIP and 4.17 xFIP in June are not really all that encouraging.

No obvious answers are on offer here. With Chris Perez seemingly a ways off from being ready to return, Cleveland needs the pre-2013 Pestano. Given Pestano’s struggles this year, it is worth watching to see if the old Vinnie is still in there.