Boston righthander Curt Schilling took a significant step in his effort to return from an injured right shoulder when he threw 25 pitches off a bullpen mound at Fenway Park.

Yesterday's session was the first time Schilling had thrown off a mound since he was placed on the 60-day disabled list during spring training.

Red Sox manager Terry Francona said Schilling's sole complaint was that only 22 of the 25 pitches were strikes.

"He was excited, justifiably excited," Francona said. "When he starts talking about hitters and, 'I'm going to do this,' then he's feeling good about himself and that's exciting for us."

Francona said the 41-year-old veteran will head back to the mound tomorrow, planning to throw 35 pitches.

Schilling signed a 1-year, $8 million, incentive-laden contract with the Red Sox last Nov. 8 before being diagnosed with right shoulder weakness.

He decided against surgery and has been steadily building toward throwing off a mound in the weeks before the first formal session, including shoulder and arm exercises.

Noteworthy

* Esteban Loaiza, a 21-game winner for the Chicago White Sox 5 years ago, returned to the team as a free agent, after being cut by the Dodgers last month.

Loaiza made 55 starts for the White Sox from 2003-04. He was the AL's starting pitcher in the 2003 All-Star Game at U.S Cellular Field, and went 21-9 with a 2.90 ERA.

In another matter, manager Ozzie Guillen might have patched things up with general manager Ken Williams after his latest outburst, but now hitting coach Greg Walker is apparently unhappy with the loquacious manager's most recent tirade.

"I'm not going to comment on that. I'll tell you this, Ozzie Guillen wants the Chicago White Sox to win and I want the Chicago White Sox to win. That's all there is to it," Walker said.

They are former teammates and friends, but Walker apparently was upset after Guillen mentioned him during Sunday's rant in which he called for Williams to make some changes in the offense.

Guillen said he hadn't talked to Walker about anything other than some routine baseball stuff and nothing about his outburst.

In games yesterday:

* At Boston, Josh Beckett (6-4) allowed a run in six strong innings and the Red Sox won their 12th straight home game to take the AL East lead from Tampa Bay with a 5-1 win over the Rays. Beckett's left foot appeared to slip as it landed on a pitch to Cliff Floyd in the sixth inning, but the team said he was fine.

* At Chicago, Paul Konerko hit a two-run homer with no outs in the 15th inning as the White Sox outlasted Kansas City, 6-4.

* At New York, Mike Mussina (9-4) allowed a run on five hits in six innings and Derek Jeter singled in the third inning to surpass Mickey Mantle for third place on the Yankees' hits list, with 2,416, in a 5-1 win over the Toronto Blue Jays.

* At Seattle, Torii Hunter hit a two-run single in a three-run first inning before Jered Weaver (5-6) and three relievers preserved the Los Angeles Angels' 5-4 victory over the Mariners.

* At Minneapolis, Joe Mauer homered and drove in three runs, as the Twins defeated the Baltimore Orioles, 7-5.

* At Arlington, Texas, Ryan Garko drove in a career-high six runs, David Dellucci hit a three-run homer and Cleveland beat the Rangers, 15-9.

* At Oakland, Justin Duchscherer (5-4) allowed three hits over 6 2/3 innings and the Athletics completed a three-game sweep of the Detroit Tigers with a 10-2 victory. *