MIAMI GARDENS, Fla. - More than a month after being hit on the left elbow with a Tim Hudson pitch, Placido Polanco is still hurting. And that is a concern for the Phillies.

Polanco will have an MRI exam on Sunday to see if there is something causing the inflammation and soreness in his lower left triceps. The Phillies third baseman has played through the pain at times in the last month, but he aggravated the injury Thursday in New York and has not played since.

"The MRI is going to be the answer to everything," Polanco said. "We'll see how bad it is, what it is, and if it can get worse. We'll go from there."

Polanco was hit on the elbow by Hudson in the first inning on April 21. He came out of the game in the seventh and missed only the next game.

An X-ray during the game showed no fracture, but Polanco said Saturday it did show something that could have been an old bone chip. But it was inconclusive, and Polanco has treated the injury with anti-inflammatory medication and regular icing.

Polanco hasn't swung a bat since Thursday and has just been throwing and doing shoulder exercises.

"It's been bothering me ever since I got hit," Polanco said. "It comes and goes. I've been able to play. But sometimes I swing and miss and it seems like I hyperextend my elbow and it feels weak."

The most recent aggravation came Thursday when he leaped for a line drive.

When Polanco first returned from the injury in April, he wore a protective pad on the elbow but struggled at the plate. In the eight games following the injury, Polanco was 3 for 32.

Polanco said he thinks he rushed his return.

"I only missed one game, and I came back too soon," Polanco said. "I was weak. I couldn't really do it."

He ditched the pad for a sleeve he's been wearing since. In May, Polanco is hitting .313 with a .821 OPS.

If Polanco has to go on the disabled list, the Phillies will have lost their entire left side of the infield to injury. Shortstop Jimmy Rollins (strained right calf) has been on the disabled list since May 22. He is eligible to come off June 6.

Should the Phillies need to call someone up, major-league veteran Cody Ransom is the likely candidate. He has 10 home runs at triple-A Lehigh Valley but is hitting .239 and has made 14 errors in the field.

On Saturday, Juan Castro (.601 career OPS) started for the first time at third, and Wilson Valdez (.573 career OPS) played shortstop and batted second again.

It was only the seventh time in Valdez's career that he batted second, but Phillies manager Charlie Manuel said he liked the shortstop there. Valdez was 2 for 4 with a stolen base Friday.

"He has talent. He can run. He can handle the bat," Manuel said. "He tried to hit the ball into the hole in right field [Friday]. That's the sign of a guy who knows how to play, and he tries to play right."

Valdez said he was just trying to do what Polanco would in the No. 2 hole.

"When they give you that opportunity, you have to do something similar," Valdez said. "He's a good hitter. I'm just trying to help as much as I can. [Friday] night, I think I did a very good job and helped the team."

Extra bases

Righthander Brad Lidge (elbow inflammation) threw a scoreless inning in a rehab outing for single-A Clearwater in Port St. Lucie, Fla., on Saturday. Lidge struck out one batter and did not allow a baserunner. He could be activated for Monday's game in Atlanta. . . . The Phillies' 30-inning scoreless streak that ended Friday was 12 innings short of the franchise record, 42, set in 1983.