NEW YORK -- Eduardo Nunez, playing his first game in two months, hit a tie-breaking run-scoring single in the sixth inning Saturday to cap a comeback victory by the New York Yankees, who beat the Baltimore Orioles, 5-4, in front of 42,678 at Yankee Stadium.
Nunez, who sustained a left oblique strain on May 5 and was activated from the disabled list before Saturday's game, finished 2-for-3 with two singles and hit a sacrifice fly during the Yankees' two-run second inning.
The Yankees (48-39) won their season-high sixth straight game to move into second place in the AL East, a half-game ahead of the Orioles (48-40).
Baltimore has lost three in a row and four of its last five.
The Yankees had 10 hits, all singles off Orioles starter Chris Tillman (10-3). New York was behind, 3-0, in the second and later, 4-2, but tied the game, 4-4, with two runs in the fifth.
Lyle Overbay had three singles and a run scored for the Yankees while Luis Cruz, Ichiro Suzuki and Robinson Cano each had an RBI.
Andy Pettitte overcame a rough first couple innings to earn his 251st career victory. Pettitte (6-6) lasted 6 2/3 innings and allowed four runs, three earned, on nine hits and walked none while striking out four.
Mariano Rivera notched his 29th save in 30 tries this season, and the 637th of his career, with a one-hit ninth inning.
Chris Davis hit his major league-leading 33rd home run for the Orioles. Alexi Casilla had two hits and an RBI, while Taylor Teagarden had an RBI single. Adam Jones went 2-for-4, both singles.
Tillman, who had won his previous six starts and his last seven decisions overall, gave up five runs on 10 hits and two walks while striking out three in 5 1/3 innings.
The Orioles took a 2-0 lead in the first on Davis' two-run, two-out home run barely beyond the grasp of center fielder Brett Gardner. The two RBIs increased his season total to 85, tying his career high set last year.
The Orioles made it 3-0 in the second on Casilla's RBI double, which scored Nolan Reimold, who had beaten out an infield single and gone to second on Pettitte's throwing error.
The Yankees began chipping away at Tillman with two runs in the second, when Travis Hafner drew a leadoff walk before three straight singles by Zolio Almonte, Overbay and Cruz, the last of which scored Hafner. Almonte came home on Nunez's sacrifice fly
Baltimore extended its lead to 4-2 in the fourth, when J.J. Hardy led off with a double, went to third on Reimold's fly out to center and scored on Teagarden's two-out single to left.
The Yankees tied the game with a four singles in the fifth. Nunez and Stewart led off with singles, advanced a base on Gardner's sacrifice and scored on singles by Suzuki and Cano.
NOTES: The Yankees made a series of roster moves before the game. To make room for Eduardo Nunez, the Yankees placed RHP David Phelps on the 15-day disabled list because of a right forearm strain. Phelps' injury allows the Yankees to keep Ivan Nova, who pitched a three-hitter on Friday night, in the rotation. ... The Yankees also shifted 1B Mark Teixeira to the 60-day disabled list. He's out for the season following right wrist surgery. ... RHP Hiroki Kuroda, who missed his start Friday because of a hip injury, will start Sunday. RHP Phil Hughes and LHP CC Sabathia were each pushed back a day. ... Orioles RHP Steve Johnson (oblique) threw a 30-pitch bullpen session before the game. ... Orioles 3B Manny Machado turned 21 Saturday. He went 1-for-4 with a double off Andy Pettitte, who began his professional career the year before Machado was born.