BRADENTON, Fla. -- The back end of the Pirates' Opening Day rotation is not set in stone. After Gerrit Cole, Francisco Liriano and Jon Niese, general manager Neal Huntington said, the final two spots are still to be determined.
Huntington confirmed that left-hander Jeff Locke and right-handers Ryan Vogelsong and Juan Nicasio will compete for those two spots. Nicasio has been a pleasant surprise, striking out 24 in 15 straight scoreless innings to start the spring.
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His four-inning, 10-strikeout start against the Orioles on Wednesday was one of the spring's most dominant performances. He held the Twins in check and struck out eight over five innings in Monday's 2-0 win.
"You look at Cole and Liriano, and you build the rotation around them. We fully anticipate Jon Niese will be in the rotation," Huntington said Monday morning. "Locke, Nicasio and Vogelsong -- two of those three will be our fourth and fifth starters to start the season. We're going to need a sixth starter some time before we want to, and that's where it's great to have those guys ready to go."
Entering Spring Training, the rotation appeared to be Cole, Liriano, Niese, Locke and Vogelsong. To replace A.J. Burnett, J.A. Happ and Charlie Morton, the Pirates traded Neil Walker for Niese and signed Vogelsong in December.
Between those two deals, they quietly scooped up Nicasio on a one-year, $3 million deal. As a starter with the Rockies, Nicasio went 20-21 with a 5.12 ERA and 6.9 strikeouts per nine innings. As a reliever, he owns a career 3.74 ERA and averaged slightly more than a strikeout per inning.

"When we signed him, we worked off the normalized numbers coming out of Colorado. On the surface, they don't look all that pretty, but we think there are some things that we can help, whether it's approach, mechanics, our ballpark, our defense," Huntington said. "We saw a good first half from Vogelsong, and there are things we think we can help him with. And Jeff Locke, again, has put together extended stretches that are very good, and how do we help him?
"It's that combination of subjective and objective [evaluation] of what your analysts think, what your scouts think and what your coaches can go apply. We think with those three guys, we'll come up pretty well."
Given his success as a reliever last season, it seemed most likely that Nicasio would bolster the bullpen as a versatile, multi-inning reliever. That still appears to be the most likely outcome, but there is at least a chance now that Nicasio could crack the rotation.
"I don't know. I'm working hard for the chance to be in the rotation, but I can't control all that," Nicasio said last week. "I try to do my job. I can't take care of that decision."

Nicasio has pitched brilliantly, and the Pirates like what they have seen from Locke and Vogelsong. If Nicasio begins the season in the bullpen, he could make a spot start or join the rotation if someone else is pushed out by injuries or poor performance.
"We don't want to say it's a wide-open competition, yet at the same time we brought Juan here for a reason," Huntington said. "We've got a group of pitchers that we think give us some starting depth, and we'll see how it plays out."