ST. LOUIS - Ruben Amaro Jr. wore one of those patented smug looks on his face before Tuesday's game. The Phillies general manager had just demoted his fifth starter, Kyle Kendrick, without listing a replacement in the rotation for him.

"I think we know exactly what we're going to do," Amaro said. "I just choose not to tell you."

Of course, the best laid plans . . .

In the first inning Tuesday, lefthander Jamie Moyer was injured throwing a pitch. The 47-year-old pitcher left after one inning with a strained left elbow.

That only complicates things.

The Phillies sent Kendrick to triple-A Lehigh Valley on Tuesday, a day after he allowed seven runs in five innings to the Cardinals, and sounded ready to replace him with someone from outside the organization.

For now, in Kendrick's place, righthander Andrew Carpenter was recalled. Carpenter, normally a starter, was brought up as an extra arm in the bullpen - and the Phillies were lucky they made the move. He relieved Moyer in the second.

Amaro said Kendrick's spot could be filled by someone from within the organization, like J.A. Happ. Happ started Tuesday at triple A and threw 44 pitches in three scoreless innings before being removed. He is likely headed to the Phillies, who now may have to replace two starters if Moyer is significantly injured.

That means a trade could be imminent. Amaro did nothing to dissuade that notion.

"We have other balls in the air," Amaro said.

Those, presumably, are the names bandied about in the rumor mills over the last month. The Phillies have sent two different scouts to look at Oakland pitcher Ben Sheets in the last month. Sheets pitched Tuesday for the A's and would be in line to start Saturday.

Baltimore's Jeremy Guthrie, Cleveland's Fausto Carmona, and Jake Westbrook along with Chicago's Ted Lilly are other pitchers on the market.

Houston's Roy Oswalt and Arizona's Dan Haren are at the top of the list of available pitchers, but both could cost top prospect Domonic Brown, a deal the Phillies likely would not accept. They made sure to not include Brown in the Roy Halladay trade during the off-season.

But on Tuesday, Amaro once again did not rule out trading a player currently on the major-league roster - one way to acquire either Oswalt or Haren in a complex deal.

"If players were playing better, I wouldn't consider moving them," Amaro said.

Ostensibly, he is referring to outfielders Raul Ibanez and Jayson Werth. Ibanez, who has struggled and is due $11.5 million next season, is effectively immovable. Werth, a free agent at the end of this season, is a different story.

Amaro said if he has to weaken one spot on the roster to improve another, he may be forced to do it. Werth would obviously not be the player the Phillies could trade to a non-contending team looking to unload a pitcher because of his contract status. But if Amaro can somehow involve a third team in the trade talks, a contender looking to add a bat like Werth's, the Phillies could have a match.

That, of course, requires the Phillies to view Brown as an upgrade over Werth for the remainder of the season.

"We think he's getting closer," Amaro said of Brown.

Then again, Amaro admitted one trade isn't the thing that will fix the Phillies.

"If we can continue to play the way we're playing, I don't know if there's a trade to make that would make us a playoff contender," Amaro said. "We have to play better baseball or we're not going to get anywhere."

But Amaro said the Phillies will definitely be buyers.

"I view us as a team that is still going to be a contending team," he said. "But it depends on the guys in this clubhouse. It's up to them. They're going to have to make it happen as they have in the past."