NEW YORK --- The New York Yankees averted getting swept by their storied rivals from Boston
when Jason Giambi hit a walk-off single with the bases loaded off Jonathan Papelbon to give the Bronx Bombers a 3-2 victory before a Yankee Stadium crowd of 55,092.

The Yankees tied game in in the seventh when Giambi, pinch-hitting for catcher Jose Molina, took Hideki Okajima deep to center field for a 2-run homer. It was Giambi's 27th homer of the season and second of the series.

Okajima's miscue spoiled an otherwise brilliant effort by Sox starter Jon Lester, who went 6.2 innings and allowed just 1 run on 5 hits while ringing up 8 strikeouts.

Closer Mariano Rivera made his first appearance of this three-game set when he emerged from the bullpen with two out in the eighth _ to the muscial accompaniment of Metallica's ``Enter Sandman'' _ and induced Kevin Youkilis to fly out to center.

Justin Masterson, who relieved Okajima with two out in the bottom of the eighth, came in and struck out Alex Rodriguez, who fanned for the third time in the game.

Masterson, however, found himself out of the game in the ninth when he gave up a single to center to Xavier Nady and walked Hideki Matsui (intentionally) and Ivan Rodriguez (unintentionally) to load the bases for Giambi.

Papelbon came into the pressure-packed situation with one out (Robinson Cano's sharply-hit line out to Jed Lowrie) and gave up the winning hit to Giambi.