Colorado Rockies closer Huston Street has biceps tendinitis in his pitching arm and is being shut down for an undetermined amount of time.

Street said he first felt discomfort Tuesday night when he threw a six-pitch ninth inning against the New York Mets in his first action in a week. He brushed it off as the effects of a weeklong layoff.

He tested out his arm before the game and said it didn't feel any worse. But he couldn't get loose in the bullpen during Colorado's eighth-inning rally, so left-hander Franklin Morales filled in and recorded his first major league save Wednesday night.

Colorado's 5-2 win over the Mets allowed them to stay atop the NL wild-card standings.

Street, who has 33 saves in 34 chances, said he expects to be out a few days but no longer than a week.

Street said he understood manager Jim Tracy's decision to shut him down now rather than risk a longer layoff by letting him try to work through the injury.

"If left up to me I'd have been one to jog out there," Street said.

But ...

"They made the right call. Obviously, it's not easy to live with," Street said. "But they've got to do what's best for the Rockies and we've played way too good a season for me to go out there and try to be a hero and muscle up."

Street said he would likely rest for a couple of days and try to play toss by the weekend.

"There's really no timetable right now," he said. "We've got the pieces to fill in for a little while."

The Rockies have been snake-bit while trying to fend off San Francisco in the NL wild-card chase.

First, they lost ace Aaron Cook to a strained pitching shoulder last week, then Carlos Gonzalez, whose hot bat in August powered Colorado into the wild-card lead, missed crucial games against the Giants and Dodgers with a hand injury and center fielder Dexter Fowler went on the DL after fouling a ball off his right knee.

Street took a week off when the Rockies went several days without a save opportunity, a stretch that included a five-game losing streak.

"When you haven't thrown for seven days, you don't expect your arm to feel the same," Street said. "Late in the season especially you always feel better when you're getting consistent work. But there were no save situations. And late in the season, too, you don't need to just get some work in _ and coming off of throwing seven out of eight games, the rest seemed in order.

"That's why it's kind of a shock to me."