With Spring Training just around the corner, it's time for an in-depth look at the Pirates' roster. This is the fifth of a six-part series checking in on each position. After covering their catchers, first basemen, infielders and outfielders, let's look at the rotation.
PITTSBURGH -- The Pirates are betting on their rotation's potential this year -- the potential for greatness from their top-of-the-rotation arms and prospects, and the bounceback potential of three other starters.
The Opening Day rotation will be led by the formidable one-two punch of Gerrit Cole and Francisco Liriano. They will be followed by Jon Niese, Jeff Locke and Ryan Vogelsong, all three hoping for a return to form. Waiting in the wings are highly touted right-handers Tyler Glasnow and Jameson Taillon.
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"There's no question some guys are going to have to step forward and pitch with a little more consistency," Pirates general manager Neal Huntington said. "Some guys are going to have to step up and come out of our system and help us over the course of this year."

Cole, 25, thrived in his first full, injury-free season, finishing 19-8 with a 2.60 ERA and 202 strikeouts in 208 innings. The former top Draft pick placed fourth in the National League Cy Young Award voting, announcing his arrival as an ace.
But Cole's All-Star season ended on a bitter note. He allowed four runs in five innings and lost to the Cubs in the NL Wild Card Game -- a defeat that certainly will motivate Cole this year.

Last season, Cole and Liriano (12-7, 3.38 ERA, 205 strikeouts in a career high-tying 31 starts) were complemented by A.J. Burnett in the first half and J.A. Happ down the stretch. Burnett has retired, and Happ signed a three-year, $36 million deal with the Blue Jays.
That led the Pirates to Niese, acquired from the Mets in exchange for Neil Walker. The lefty was bumped to the bullpen last season by the Mets' cadre of young aces, ultimately posting a 4.13 ERA over 176 2/3 innings, but his career ground ball rate of 50 percent fits the Pirates' profile.

Locke, 28, recorded a 4.49 ERA in 30 starts last season. He is working with pitching coach Ray Searage to tweak his delivery, removing the dramatic spin in his windup and believing it will lead to more consistent results.
The Pirates essentially replaced inconsistent right-hander Charlie Morton (traded to the Phillies) with Vogelsong (signed to a one-year deal). The 38-year-old right-hander will return to Pittsburgh, where he pitched from 2001-06, after reviving his career with the Giants. Vogelsong showed flashes of his 2011-12 form last season but ended the year with a 4.67 ERA in 135 innings.

Glasnow and Taillon will start with Triple-A Indianapolis, as Glasnow continues his development and Taillon gets back on the mound after two years marred by injuries. But they will pitch in the Majors at some point this season, taking their place in Pittsburgh's rotation and remaining there for years to come.
But for now, the back end of the Pirates' rotation will enter the year saddled with questions. Can Niese step up as a No. 3 starter? Will Locke be more consistent? What will they get out of Vogelsong?

Beyond Cole and Liriano, do they have enough to keep up with the Cubs and Cardinals?
"They've got the talent and the stuff to be consistent starters in the Major Leagues and help the Pirates," Searage said.