Marlins officials, including Guillen and pitching coach Randy St. Claire, talked about the closer situation before facing the Mets on Wednesday night at Citi Field.
Steve Cishek has been handling the ninth inning, and the 26-year-old right-hander logged his seventh save after retiring the side in order in the ninth inning on Tuesday.
Cishek is shaping up as the closer of the future, but Bell was signed to a three-year, $27 million contract because he was one of the top closers in the game from 2009-11.
While with the Padres, his 132 saves in his final three seasons in San Diego were the most in the Majors.
Since the All-Star break, Bell has made 10 appearances, and he's given up three hits in nine scoreless innings.
"We talked about it today," Guillen said. "I like the way he's thrown. I think Heath Bell, I've said it from the beginning, that we're a better ballclub when he was closing."
Ideally, the Marlins want Bell to close because it allows Cishek to be used in multiple innings. Bell is a one-inning pitcher.
"It gives me Cishek to close the seventh and start the eighth," Guillen said. "With Bell, I can't, because he's not that type of pitcher. We talked about it today, that we might flip-flop them to see how that works."
Bell was relegated to a setup role after converting 19 of 25 save chances in the first half.
The right-hander credits the turnaround to fixing his mechanics. Basically, he observed that his lead foot stride was about three inches too far.
"I've fixed my mechanics," he said. "There was something wrong all year, and I've fixed it. You could say right at the All-Star break, I realized what I was doing. I was just working on it. I feel like the person I was before. Mechanically, there was something wrong.
"You don't go from the top of the game to the bottom of the game, unless there was something wrong. Mechanically, I figured out what it was. ... My stride was too long. It was too long by two to four inches. As soon as I shortened up my stride, everything clicked. I created a bad mechanic in the spring, and nobody caught it."
Before Guillen told the media that he was leaning toward going with Bell as closer, the veteran didn't think he was going to get another shot to polish off the ninth.
"Do I want to close? Yes," Bell said. "Is Steve doing a great job? Yes. I'm here. If Ozzie wants to put me in the game, in the seventh, fifth, first, ninth, I'm going to do whatever he says.
"I found out I need to really listen to myself. I can't listen to anybody. I'm my own best coach, unfortunately. I'm not trying to take anything away from St. Claire. I'm not saying he's bad. I'm not saying that. I'm just saying my pitching style is unique. And I need to figure it out. And I figured it out. I was looking for help, and I should have been looking for help from myself."