Ruben Amaro Jr. said he'll likely be searching for a center fielder if the Phillies' worst fears are realized Monday when Ben Revere's fractured right ankle is examined by a foot specialist at Jefferson Hospital's Rothman Institute.

"The prognosis doesn't sound too good," the general manager said before Sunday's game against the Chicago White Sox. "We'll see how long it's going to be. I think it's something that's going to take a while. If that's the case, we'll probably be looking for a center fielder if one is available or will be an upgrade on what we have with John (Mayberry) out there."

The most interesting option is already in the organization. The Phillies decided last week to start taking a look at triple-A Lehigh Valley second baseman Cesar Hernandez in center field. When Amaro was asked about grooming him for the position he did not count it out. In fact, the Phillies have decided to accelerate his learning curve.

"We're moving Cesar to double A (Monday) from triple A," Amaro said. "He'll play center field every day for the next 10 days or so. We're going to get him extensive work down there. He'll be at Reading through the break, then back to Lehigh Valley at some point. But he'll be playing exclusively in center field to see if that's an option for us. He struggled (Saturday), but it's a new position for him. We'll give him a shot."

In four games as a center fielder, Hernandez had nine chances and one error. Hernandez, 23, had previously played one game professionally as a center fielder and that was as at age 17 in the Venezuelan Summer League.

Hernandez, is an interesting option to replace Revere because the two have similar games based on their ability to run. In a brief stint with the Phillies while Chase Utley was on the disabled list earlier this season, Hernandez hit .250 (7-for-28) with a double, an RBI and two runs scored.

He continued to play well after returning to Lehigh Valley and was scheduled to play in the triple-A all-star game Wednesday in Reno, Nev. Instead, he'll be playing center field in Reading in the hope that he'll soon be in the big leagues playing the position for the Phillies.

Amaro made it clear before the Phillies' final game before the all-star break that he is currently more interested in adding big-league players before the trade deadline.

"We're looking for two areas pretty specific," Amaro said.

The bullpen and center field are the areas.

The Phillies are going to be reluctant to deal young prospects, but Amaro said "there are some young players that we might be able to use. We can't afford to move guys that we think are close or going to be helping us here shortly."

Amaro was blunt when asked how the Phillies could be contenders with Ryan Howard and Revere on the disabled list for an extended period.

"Well, we'll find out," he said. "I'm the GM. I'm supposed to be able to do that stuff. It's pretty exciting actually for us to have gotten ourselves back in the race and have been playing a little bit better baseball has been great. The starting pitching has been outstanding. … It's nice to see guys improve.

"Ben Revere has obviously given us a lift. Michael Young's come up with some really big base hits for us. John Lannan's pitched great for us. And some of the guys that we were hopeful to count on in the early part of the season and weren't, they've kind of picked it up. Delmon Young's come up with some big base hits for us. We just have to have our guys continue to play. We've got to pitch. If we don't pitch, we don't have a shot at it. But we've pitched pretty well, we've played a little bit better baseball and no one's run away from us."