ST. PETERSBURG, Fla. (AP) -With Gary Sheffield and Mariano Rivera healthy again, the New York Yankees look even more formidable in their quest for the best record in the American League and homefield advantage in the playoffs.

A ''nervous'' Sheffield returned to the lineup for the first time since May 29 and made an impressive debut at first base Friday night. The ever steady Rivera earned his 34th save in his first appearance since Aug. 31, helping the AL East champions beat the Tampa Bay Devil Rays 4-1.

''I'm treating this like the World Series right now because I've got to be ready when it comes to the playoffs,'' Sheffield said, conceding he had some anxious moments in his first game at a new position.

''He was nervous,'' shortstop Derek Jeter said of the longtime outfielder. ''He said he doesn't remember being that nervous before.''

Rivera, meanwhile, shrugged off some initial rust and struck out the side around a broken-bat single and a hit batter in the ninth.

''I was anxious. I couldn't wait to pitch,'' said Rivera, sidelined with a strained right forearm. ''I'm happy I went in there and finished the way I wanted.''

Sheffield, who had seven putouts, saved a run with the score tied 1-1 by scooping third baseman Miguel Cairo 's low throw out of the dirt to end the sixth with a runner on third. He also handled a low throw from Jeter in the fourth.

''It looked like he had been there a lot longer than just working out this past week,'' Yankees manager Joe Torre said.

''I thought he reacted real well to when the ball was hit. That's what you really have to get used to. When you're playing third or playing short or the outfield and the ball is hit to somebody, you watch it unless it's hit to you. But as a first baseman, when the ball is hit you've got to go to the bag. He didn't have any trouble reacting to that.''

The nine-time All-Star went 0-for-3 before leaving the game after the Yankees took a three-run lead in the seventh.

''Sheff is a good athlete, that's the thing. He came up as a shortstop. He played some third,'' Jeter said. ''Footwork, knowing where to be, that will take a while for him to get used to.''

Robinson Cano and Aaron Guiel homered to back starter Chien-Ming Wang (18-6), who allowed six hits in seven innings, including Rocco Baldelli 's solo homer in the first. He struck out four to improve 3-0 this season against Tampa Bay.

The victory in New York's first game since clinching its ninth straight division title on Wednesday night improved the Yankees' record to 93-60. The last-place Devil Rays tied an AL record by losing for the 57th time after holding a lead.

''They've got a nice thing going on. They're healthy. They're playing probably better than anybody else in the league right now,'' Devil Rays manager Joe Maddon said. ''They're playing at a high level, and everybody's getting well for them at the right moment.''

Sheffield missed 103 games during his second stint on the disabled list this season with a wrist injury. He had surgery June 13, and worked out at first base during his rehabilitation.

With the division title in hand, the Yankees gave the night off to Alex Rodriguez , Hideki Matsui and Bobby Abreu . Johnny Damon was scratched as a precaution for the second straight game after cutting his throwing hand making a diving catch at Toronto on Tuesday, and Jason Giambi may sit out the entire four-game series with a small ligament tear in his left wrist.

How well Sheffield does at first base could impact the Yankees' postseason roster. If the move works out, Matsui could move back to left field and Giambi ideally would enter the playoffs as the designated hitter.

James Shields (6-8) retired the first 10 Yankees before Cano homered with one out in the fourth.

The Yankees broke the tie in the seventh. Bernie Williams singled with one out and scored on Guiel's first homer since July 25. Cairo singled for the third straight hit off Shields and scored when Melky Cabrera doubled.

Shields allowed four runs and eight hits in seven innings. He struck out six and walked none.

Notes: Jeter had a bunt single in the eighth, giving him his fifth 200-hit season. He and Lou Gehrig (eight) are the only players in franchise history with at least four. ... Yankees RHP Kyle Farnsworth warmed up in the eighth but was unable to pitch because of back tightness, a problem he's had off and on this year. ... The 2002 Tigers also lost 57 games in which they led. The major league record is 66 by the 1998 Marlins. ... Devil Rays 2B Jorge Cantu was scratched from the lineup with a fever.