Tonight's start is an audition for Chase Whitley

Joe Girardi's official reasoning for calling up Chase Whitley to start tonight's game against Tampa Bay was to take some pressure off a rotation that's nearing the end of a 13 game in 13 day stretch and in the midst of one that features 30 contests in 31 days. Even after an excellent 5.2 inning, six strikeout performance from reliever turned fifth starter Adam Warren last night, though, the manager will be paying close attention to see if Whitley can give him another option at the back of the rotation. Warren will likely retain the job for now, but given the volume of approaching games and the risky nature of the Yankees' other starters, Whitley's fighting to stay ahead of Bryan Mitchell as the next option if a sixth starter is needed again or if one of them goes down. A decent outing from Whitley may prevent him from heading straight back to Scranton. A really good showing could put that ticket on permanent delay.

Whitley, a converted reliever himself, made a strong entrance to an injury-besieged Yankee staff last May, allowing three or fewer runs in each of his first seven starts and posting a tidy ERA of 2.56 and a 1.03 WHIP in that span. Then in Toronto on June 23rd, things took a bad turn. Whitley faced 24 batters in just 3.1 innings that game and let 14 of them reach base. He got demolished for eight runs on eleven hits, and in his next couple of starts, didn't fare much better. Boston clobbered him for eight hits and five runs in four innings on the 29th, and Whitley was a dud on July 4th, allowing eight more hits and four runs in three innings against Minnesota. He made two more starts in July, and despite a quality outing against Texas on the 22nd, spent the rest of the season in the bullpen and in the minors.

Despite his rough finish last year, though, there's reason to believe Whitley might make it as a Major League starter. Much of his struggles in 2014 were BABIP-related as hitters scored a .353 average on balls in play. Having the ghosts of Derek Jeter and Brian Roberts up the middle doesn't help when you're trying to get outs in the infield. Whitley's 5.23 ERA was ugly, but it came alongside a decent 4.14 FIP and an even better 3.77 xFIP, which were thanks to a 7.14 K-per-nine rate and a 2.14 walk rate. Though his 20.8% line drive rate could improve, a 45.3% ground ball rate is workable, especially in front of the Yankees' improved defense.

At 25, Whitley's been outstanding so far this season, albeit not on the big stage. He had a 1.17 ERA and 1.04 WHIP in 15.1 innings in spring training and continued that progress through his first three starts for Scranton, notching a 2.12 ERA and 2.83 FIP. Whitley's not exactly a flame thrower - his fastball averaged 90.7 on the gun last season - but thanks to a slider and change which comprise more than half his pitches, he's deceptive enough to get swings and misses, doing so at an 11.1% rate in 2014. You don't need lights-out stuff to be successful if you're able to keep free passes to a minimum and keep the ball on the ground. Warren's done well at the latter this season, but not the former, at least not before last night. Now we'll see if Whitley can do better.

In only his second season as a regular starter, Whitley isn't going to be the front of the rotation piece that the Yankees may need to truly contend this year. Still his recent minor league success and his strong peripherals last year suggest he may ultimately prove a better number five than Warren and eventual returnees Chris Capuano and Ivan Nova.