Bell, 35, signed a big contract with the Miami Marlins as a free agent in the offseason, with the team expecting him to fill the role of closer.

The veteran struggled mightily out of gate, posting an 0-3 record with two saves and an ERA of 10.80 in April, and a 2-5 mark with a 6.75 ERA before the All-Star break.

He was yanked from the closer role after recording just 19 saves.

The second half of the veteran's season was much better -- it could not have been much worse -- as he went 2-0 with a 3.10 ERA in 29 innings of work.

That's the pitcher the D-backs believe they acquired, and it's the guy Bell thinks he's ready to be for his new team.

"I just think every great player has a down year, and it's really how you react the next year," Bell told a media gathering Friday at the D-backs Golf Classic. "I'm trying to get in the best shape possible and just trying to work real hard and cross the t's and dot the i's."

Bell established himself as one of the game's premier closers with the San Diego Padres. D-backs GM Kevin Towers was running the team then, and Bell credits him for giving him a chance to show his stuff.

That stuff, Bell said, was not lacking last season and should not be an issue going forward.

"There was just other stuff that happened that I really don't want to talk about," Bell said. "I just want to talk about my future with the Diamondbacks and this upcoming 2013 season."

Bell was part of an underachieving Marlins team that spent wildly in free agency only to finish last in the NL East with a 69-93 record. Outspoken and controversial manager Ozzie Guillen was fired after just one season with the team.

Away from that mess, Bell, who comes to the Diamondbacks with a career ERA of 3.30 and 153 saves, says he'll be happy to fill whatever role his team needs him to.

"Whatever they tell me to do, that's what I'm going to go out and do," the three-time All-Star said, noting that J.J. Putz is the team's incumbent closer and he may be needed earlier than the ninth inning most nights. He's fine with that.

"My role is to when the phone rings and my name is on the end to go out and get as many guys out until they pull me out of the game."