KANSAS CITY, Mo. -- New York Yankees outfielder Bernie Williams will likely miss 4-6 games because of recurring soreness in his ribs.

"He said it doesn't feel as bad as it did the last time, which is encouraging," manager Joe Torre said Tuesday before the Yankees' 10-5 victory over the Kansas City Royals. "Hopefully, maybe it was just something that was left over.

"I'm not planning on him for the rest of this trip, let's put it that way."

The immediate future of right-hander David Cone is also in doubt after he separated his left shoulder diving for a bunt in Tuesday's game.

Williams, who has 111 RBI and needs 19 to tie the single-season record for a switch-hitter, missed seven games from Aug. 19-25 with strained muscles in his right rib cage, an injury sustained in batting practice Aug. 19.

On Monday, Williams hurt himself again swinging at a forkball from Kansas City starter Mac Suzuki in the first inning of the Yankees' 4-3 win. After striking out swinging to end the inning, Williams played the bottom of the first in the outfield before being replaced by Clay Bellinger.

Williams dressed for batting practice Tuesday but did not take any swings.

"I'll just be out there stretching, maybe doing some shagging," he said. "No swinging -- it's frustrating."

Before getting hurt for the first time, Williams had started the Yankees' first 118 games of the season.

"He's a durable player," Torre said. "He's one of those guys you just write in the lineup -- you don't even think about it."

Cone was taken to the hospital for X-rays, which revealed no damage. An MRI taken on his left shoulder Wednesday morning showed no structural damage, only bruises associated with an anterior dislocation.

Cone has been scratched from his next scheduled start Sunday, but there was no word on his status beyond then.

"Judging from how it feels now, I was pretty lucky," Cone said.

The prognosis was brighter for the return of reliever Ramiro Mendoza.

Mendoza, who has been plagued by tendinitis in his right shoulder and has not pitched since July 29, threw more than 50 pitches in a simulated game Monday. He could get some bullpen work against Kansas City.

"He's sore in all the appropriate places, and that's good," Torre said. "I don't know about tomorrow, maybe Thursday. We'd definitely like to have him get a game under his belt here."

Right fielder Paul O'Neill continues to improve after missing six games in late August with a right hip pointer. O'Neill made a long run to grab Jermaine Dye's foul ball in the eighth inning of Monday's game.

"That was a good play to get to that ball," Torre said.

The Yankees also called up LHP Randy Keisler and INF Alfonso Soriano from Triple-A Columbus. To make room for Keisler on the 40-man roster, the Yankees placed RHP Darrell Einertson on the 60-day DL.