CLEVELAND -- The Indians' bullpen has not been on a defined roll this season because it's been a struggle for the Tribe's relievers to establish defined roles.
With closer Joe Borowski on the 15-day disabled list, the Indians know that setup man Rafael Betancourt is their current closer.
The rest of the picture is muddled, and the results have been muddy. The Indians entered Friday with the third-highest relief ERA in the American League with a 5.07 mark. Their .294 average against relievers was the highest in the league.
"I'm not satisfied," manager Eric Wedge said. "We need to do better. I think some guys are doing a decent job, and others aren't."
Wedge said he's pleased with the way Japanese import Masa Kobayashi has stepped into a more prominent role lately. Kobayashi has allowed one earned run over his past 5 2/3 innings, and he's been used in tighter situations as the month has progressed.
"Masa's really pushed his way up the ladder," Wedge said. "He's not your typical first-year guy, but it's still his first year."
Jensen Lewis' first year, 2007, saw him work his way to the bullpen's back end, where he's remained this season. The results have been a little more uneven this year, though, and Lewis has given up four earned runs in his past 8 1/3 innings.
Left-handed setup man Rafael Perez has struggled some after a dominant '07,having given up three earned runs over his past 5 2/3 innings.
Veteran addition Jorge Julio has struggled with his control, issuing six walks in 10 innings, while Craig Breslow and Tom Mastny haven't gotten enough work to make a significant contribution.
The bullpen mix was stable coming into the year, but the Indians knew they would have to tweak things as necessary.
"You come into the season reserved, but you have an idea of who's going to start out in what role," Wedge said. "We've had to make some adjustments, whether it be performance, or the injury with Borowski. We're working through it."
Anthony Castrovince is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.