"It's three saves in a week. It's four out of eight," manager Clint Hurdle said Thursday. "I've watched a volume of work. Take it from there. It's apparent to me that we need to shuffle the deck."
Hurdle talked to Corpas and Fuentes before Thursday's game against the Chicago Cubs. Hurdle said Corpas has lost velocity.
"We are seeing the inconsistencies. You need to find a way to help him," Hurdle said.
Corpas, 0-1 with a 7.50 ERA, has struggled after going 3-for-4 in save opportunities to start the season. Against Philadelphia on Tuesday, he allowed a go-ahead, three-run double to Pat Burrell in the ninth inning. The following day, he gave up a two-run, ninth-inning homer to Aramis Ramirez during a game that the Chicago Cubs won in 10 innings.
In Colorado's 2-1 win over San Diego last Thursday -- a game that went 22 innings -- Corpas blew a save chance in the 14th.
"I'm going through a bad spot, like all baseball players do," Corpas said through an interpreter after Wednesday's game.
Fuentes is a three-time All-Star who was the closer for three years before losing the role midway through last season. He became Colorado's closer early in 2005 and saved 30 games. He followed that with a 31-save season in 2006, but after Fuentes failed on four straight save chances last June, Corpas took over as closer in early July.
Corpas was 19-for-20 in save chances, then went 1-0 with five saves in six chances during the postseason, compiling a 0.87 ERA in nine appearances.
Now he will go back to being a setup man for Fuentes, who understands what Corpas is going through.
"You learn life does go on," said Fuentes, 0-1 with a 2.45 ERA in 12 appearances. "When you blow one save, it's like the world is coming down. Then, it's two. Fortunately, he didn't blow four in a row like I did. He's going to be fine."
Hurdle didn't say whether the switch was permanent.
"I don't see the sense it ever makes in painting yourself into a corner," Hurdle said. "You have to do what's best for the club. That's to give the ball to Brian right now, get the heat off Manny and give him an opportunity to work his way out of this and see how that plays out."