Blue Jays closer Sergio Santos has come full circle.

He's back with the organization where he spent three seasons trying to make the major leagues as a shortstop.

This time around, his role is much different.

Santos converted to pitching in 2009 and will serve as Toronto's closer this season, taking over a role that departed relievers Jon Rauch and Frank Francisco split last year. Armed with an impressive fastball, slider and change-up, Santos is ready to build on the impressive 2011 season he had with Chicago.

"My mindset is the same," Santos said Tuesday. "I'm going to attack, attack, attack."

The Blue Jays gave up pitching prospect Nestor Molina to acquire the 28-year-old Santos in a trade with the White Sox at baseball's winter meetings.

Santos earned 30 saves in 36 chances last year, going 4-5 with a 3.55 earned-run average in 63 games. The six-foot-two, 230-pound right-hander is a strikeout pitcher, fanning 92 in 65 1-3 innings.

He made a major-league record 25 straight scoreless appearances on the road to start the season.

"He gives himself a pretty good starting point when you can have those three types of pitches and almost a fearless approach towards attacking a hitter," said manager John Farrell. "Maybe the fact that he was a hitter in the past — he knows how hard it was to hit.

"So it might give him some innate confidence when he takes the mound equipped with that repertoire."

At first, he wasn't thrilled when Buddy Bell — then the director of player development with the White Sox — suggested he give pitching a try.

"It's a tough process just because you're starting all over with something," Santos said. "The last time I had pitched, I was 12 years old."

Santos had a strong, fresh arm and decided it was worth a shot. While it was challenging at times, he started to feel good about the switch a few weeks into the conversion.

"I kind of felt like, 'You know what, if I get this right I think it can turn into something,"' he said. "I just had this belief, this confidence that it will work out."

In 2010, the Bellflower, Calif., native went 2-2 with a 2.96 ERA, one save and 56 strikeouts in 56 games with the White Sox.

"Things kind of took off quickly and I was able to pick it up somewhat fast," Santos said. "I'm excited. I feel like there's so much more that I can learn and hopefully the sky's the limit for me."

Santos had signed a US$8.25-million, three-year contract with the White Sox shortly after the end of the regular season. Blue Jays general manager Alex Anthopoulos also landed setup man Francisco Cordero in the off-season, signing the free agent to a $4.5-million, one-year deal.

Gone are the days of closer by committee, a plan that did not work out last year.

"I think the revolving door in the closer position really led to an uncertainty in the bullpen," Anthopoulos said. "It was tough and that one's on me because those are the guys I gave John to work with. I think now having more defined roles is going to helps things.

"And I just think there's also a ton of talent in that bullpen too. So I definitely feel a lot better."

Santos said knowing your role helps everyone in the bullpen.

"Whenever you have structure it's always a little more organized, it's a little bit better, it's a little more efficient, easier to manage," he said. "So with that it just makes it easier knowing if it's a tight ball game, we know who's coming in.

"If it's not a tight ball game, then we'll find something else out."

Santos is friendly and quick with a smile. And why not, when the comfort level is this high.

"It just feels energizing here," he said. "It feels like a breath of fresh air. We've got a young core but a motivated core. Guys that are ready to get after it and sprinkled in with some veterans that go about their business the right way.

"So it's good for the young guys to learn and it's exciting. You have a different feel coming into this spring than past springs."