NEW YORK - Mariano Rivera's day had been filled with so much sadness, a funeral for relatives in Panama followed by a lonely flight back. Then, after the New York Yankees' lead dwindled from eight runs to one, the bullpen doors in left-center field swung open and out he came.

His teammates needed him, the fans expected him and the situation demanded him. And so the greatest closer in baseball put aside his grief just long enough to do what he does best: save the day.

Rivera stopped the surging Boston Red Sox yet again Tuesday night. He got Kevin Millar to pop out to strand the tying run at third base in the eighth inning, then finished out a thrilling 10-7 win for the Yankees in the AL championship series opener.

"I came here and my friends, my teammates treated me like a king, and that was something special," Rivera said, even more soft-spoken than usual. "I wanted to stay home and stay with my family, but I have a job to do, and I have 24 players that were waiting for me."

On a night that generated the kind of excitement expected from these great rivals, Hideki Matsui tied an ALCS record with five RBI, four off Curt Schilling. The Boston ace allowed six runs in three innings and isn't sure whether his aching ankle will keep him out of the rest of the series, which continues tonight with Boston's Pedro Martinez pitching against Jon Lieber. It will be Martinez's first start in New York since he called the Yankees "my daddy" last month.

"I expect him to be on. We need him to be," said Red Sox leadoff man Johnny Damon, who struck out four times in the opener. "There's no way we can come back to Boston down 2-0."

A rematch that had been anticipated since Aaron Boone's 11th-inning homer off Tim Wakefield won Game 7 last year began with Mike Mussina retiring his first 19 batters and New York opening an 8-0 lead.

"It was like it was too good to be true," New York manager Joe Torre said.

It sure was.

Mark Bellhorn doubled on a drive that hit the left-field wall on a hop. After Bellhorn's hit on Mussina's 86th pitch, Millar had a two-run double with two outs and scored on a single by Trot Nixon. Tanyon Sturtze relieved and Jason Varitek hit a two-run homer on his third pitch, pulling the Red Sox to 8-5.

David Ortiz made it 8-7 with a two-run triple in the eighth against Tom Gordon, a ball that popped out of Matsui's glove near the top of the wall. That's when the crowd got up to welcome Rivera, perhaps the biggest factor in New York's six AL pennants and four World Series titles since 1996.

"Turns out, we really needed him," Mussina said. "I'm sure glad he came back."

Rivera returned home to Panama Sunday after two relatives were electrocuted in his swimming pool. Earlier Tuesday, he attended the funeral services, then boarded a private jet provided by the Yankees for the trip to New York. About six hours later, he was back at the ballpark, and by the fifth inning he was in the bullpen.

"It was tough coming on that plane alone," Rivera said.

When he got to the mound in the eighth, Derek Jeter spoke to him.

"Get him out," he told Rivera.

He did, with Millar popping out to the Yankees captain.

"What he did tonight was phenomenal with all the tragedy he's been through," Millar said.

Bernie Williams hit a two-run double in the bottom half off Mike Timlin, a ball that soared over Manny Ramirez in left and gave Williams three RBI.

Varitek and Orlando Cabrera made the ninth interesting with one-out singles. Bill Mueller, whose two-run homer off Rivera beat the Yankees at Fenway Park on July 24, hit a comebacker that Rivera turned into a game-ending double play. Afterward, Jeter and Alex Rodriguez gave Rivera hearty hugs and first baseman John Olerud gave him the ball in honor of his 31st postseason save.

"He's the most impressive teammate I've had in my 10 years in the big leagues," Rodriguez said.