BRADENTON, FLA. – His pitch count pushing 30 — in the first inning — Vance Worley was about to finish spring training with another poor performance, raising more questions about the strength of the Twins starting rotation.

Then Worley found his groove, retiring nine of the final 10 batters he faced. His innings hummed along and suddenly the Twins saw what they were looking for when they traded for him in December.

Worley on Wednesday found some things to build on heading into his next start — which happens to be the first game of the regular season.

The righthander has been named the Twins' Opening Day starter for Monday, when he will take the ball in a matchup with Detroit ace Justin Verlander.

"The big thing was watching our starter throw the ball," Twins manager Ron Gardenhire said. "He was sharp. Good breaking balls today. It was the best we've seen him.

"We always say 'your ace,' and for us it is the guy who takes the ball each day is our ace and we'll go from there. And he's going to get it the first day."

Worley helped the Twins beat Pittsburgh 7-4, holding the Pirates to two runs over five innings on seven hits with no walks and five strikeouts. He struggled early, throwing 27 of his 80 pitches in the first inning. Then he made a big mistake in the third, giving up a solo homer to Pedro Alvarez. After that, he got on his roll, leaving everyone impressed with his outing and optimistic about his season.

"He's a guy who gets after it and works hard," Twins catcher Joe Mauer said. "I noticed that the first day of camp."

Worley, who came to the Twins along with prospect Trevor May from Philadelphia in December in exchange for Ben Revere, finishes spring training 0-1 with a 5.73 ERA, but he pitched a little better in his past two outings. Worley responded after pitching coach Rick Anderson challenged him and other pitchers to step up their games before the team broke camp.

The Twins did not announce the rest of their rotation. After Worley, righthanders Kevin Correia, Cole De Vries and Mike Pelfrey are lined up, based on the spring rotation. Worley was penciled in to start Opening Day coming into camp, but the Twins waited until Wednesday to announce the appointment in case they wanted to make a change.

Anderson said there's a mental progression a pitcher makes during spring training as well as physical. After Worley gave up four earned runs over five innings to the Yankees on Friday, Anderson told him it was time to step up his game. And Worley responded.

"We had to talk about it, and it made my last bullpen more game-like," Worley said. "I focused on throwing it like there was a batter in there. I got a better feel for everything."

Worley will be symbolic of the changes the Twins have made to their rotation, a makeover made necessary following a 2012 season during which the Twins finished 66-96. Many of those 96 losses were games in which the starting pitcher was knocked out early.

The Twins sought innings and reliability with the offseason moves. And Worley will be the first of the new crew to debut.

"I'm excited," he said, "especially after having the spring I had. Worked some kinks out. I threw the ball well [Wednesday], with the exception of that bomb [to Alvarez], but everything went well."