NEW YORK - It took 15 innings, it took over five hours and it took one amazing swing from Jim Leyritz to finally end the marathon, as his two-run homer off Tim Belcher lifted the Yankees to a dramatic 7-5 victory over the Mariners early Thursday morning at Yankee Stadium.

After Leyritz's ball sailed over the right-center-field fence, he was greeted by a fan whose hand he slapped between second and third base, then buried under an avalanche of pinstriped teammates when he crossed the plate.

The scene was incredible, as the Yankees piled on Leyritz and tumbled around like a rugby scrum and most of the 57,126 fans who had remained through the long evening serenaded the team with ``New York, New York.''

Because of Leyritz's homer, as well as earlier homers by Ruben Sierra, Don Mattingly and Paul O'Neill, and Mariano Rivera's three and a third innings of stellar relief, the Yankees took a commanding 2-0 lead over Seattle in the three-of-five-game division series. Game 3 is scheduled for Friday at the Kingdome in Seattle, with Jack McDowell expected to oppose Randy Johnson. But the Mariners will not be able to forget their Game 2 loss soon.

``In the heat of the moment, everybody thinks it's gone,'' said Leyritz. ``I knew that I hit it far, and I was just hoping it had enough to make it over. It was a great feeling.'' The winning hit had to be particularly sweet for Leyritz, who had been hit by a pitch from Johnson in an August game in Seattle, and had promised to get even. Leyritz had been hit again, by Seattle's Bill Risley, in the sixth inning Wednesday night.

In a game in which the Yankees rebounded from deficits of 1-0, 2-1, 4-3 and 5-4, their final rally began in the 15th when Pat Kelly walked on a 3-2 pitch. Leyritz, who was only playing because Andy Pettitte was the starting pitcher, then provided the fireworks to end the night successfully for New York.

Welcome to postseason baseball, when every setback can be devastating. The Yankees found out how deadly one swing can be when Ken Griffey Jr. pounded John Wetteland's 3-1 fastball over the right-center-field fence to give the Mariners what seemed like a huge 5-4 lead in the 12th inning and temporarily deflate the fans. It was the fourth inning of work for Wetteland, who threw a season-high 50 pitches.

The Mariners found out how difficult it is to protect a one-run lead in extra innings when the Yankees tied the game in the bottom of the 12th on Sierra's two-out, run-scoring double off Belcher with runners on first and second. Sierra's sharp shot missed being a homer by about 5 feet as it caromed off the left-field fence. Alex Diaz played the ball quickly off the fence and Bernie Williams was thrown out trying to score from first base as the Yankees were prepared to spill onto the field and celebrate.

``We've got to win three baseball games,'' Showalter said before the marathon. ``We're going to have to win in Seattle. We know how tough it's going to be. The thought of going to Seattle is a formidable task.''

``Going there with a two-game lead is a big advantage,'' Leyritz said.

With the fans chanting ``Donnie Baseball, Donnie Baseball,'' in the 13th inning, Mattingly obliged them by rapping a single to center field and there were visions of a Yankee victory. Pat Kelly bunted Mattingly to second, but Leyritz squibbed a 2-0 pitch back to Belcher for the second out. Piniella elected to intentionally walk the switch-hitting Tony Fernandez and Randy Velarde was unable to spoil the strategy as he popped out to first baseman Tino Martinez for the third out.

After Griffey homered off Wetteland in the 12th, the Mariners sensed it would be their night. Why not? Griffey had whacked an important homer off Wetteland once before and it catapulted Seattle to 25 victories in the following 36 games. On Aug. 24, Griffey capped a three-run rally against the Yankees with a monstrous, two-run homer into the upper deck of the Kingdome to give Seattle a 9-7 victory. He is the player the Yankees know they must stop, but Griffey has connected for three homers in the first two games to tie an American League playoff record.

New York's impressive rally in the 12th was built on two walks. Jeff Nelson walked Wade Boggs and Belcher replaced him and walked Williams. After O'Neill popped out to left field, Sierra provided the tying run.

The game was a roller-coaster ride of emotion. If the Yankees won, they would journey to Seattle with a commanding 2-0 lead and need only to win one game at the unfriendly Kingdome. If the Mariners won, they would tie the series, 1-1, and be able to gain a potential advantage by using Johnson, their ace, in Game 3.

Pettitte, who pitched seven innings, and Andy Benes, who lasted into the sixth, were afterthoughts by the time this game was decided. Vince Coleman's homer in the first inning, the back-to-back shots by Sierra and Mattingly in the sixth and O'Neill's blast in the seventh were tucked away in the background by the time the 15th inning arrived.

Even George Steinbrenner's complaints were reduced to footnotes. The owner moaned about the umpires's calls for the second straight evening. He felt two close plays at first base went against the Yankees and also did not think Lou Piniella should have been permitted to pull his team off the field in the sixth inning after fans littered the field with bottles, cups, helmets, caps and even a grapefruit following Mattingly's first post-season homer.

``Lou's brilliant,'' said Steinbrenner. ``He's a brilliant strategist. It's brinkmanship over and over. I had him. I know him. He did that to take away the momentum and quiet the crowd down and these guys let him get away with it. He shouldn't have been allowed to do that.''

The sixth-inning celebration actually began one batter earlier when Sierra crushed Benes' pitch into the right-center-field bleachers, and performed his usual home run dance by strutting out of the batter's box and returning to the dugout much later, with the score tied, 2-2.

Before Sierra could finish describing his homer, Mattingly ripped a 1-0 pitch to almost the same spot in right-center to put the Yankees ahead, 3-2. Because it was the beloved Mattingly and because the homer gave the Yankees their first lead of the evening, the 57,126 fans at Yankee Stadium went ballistic and treated the Stadium like a garbage disposal.

But their celebration stopped when the Mariners rebounded with two runs in the seventh off Pettitte (seven innings, nine hits, four earned runs) to squeeze out a 4-3 lead. Joey Cora doubled and Vince Coleman reached on an infield single after third baseman Boggs appeared to throw him out at first. Umpire Jim McKean called the runner safe, the second close play at first base that went against the Yankees Wednesday night, and one of several calls that enraged Steinbrenner.

Luis Sojo followed with a run-scoring single up the middle that tied the score, 3-3. Griffey then hit a fly to medium left field and Gerald Williams, who was inserted into the game in place of Dion James for defense, made a weak throw home as Coleman scored easily and the cutoff by the Yankees cut down Sojo going to second.

With two out in the Yankee seventh, O'Neill, batting against the left-handed Norm Charlton, tied the score, 4-4, with New York's third homer of the game.

It was hard to not be amazed by the effort Wade Boggs has been making on behalf of the Yankees. With one out in the fifth and the Yankees producing nothing but zeros against Benes, the five-time batting champion worked an artistic at-bat in securing a walk. Despite his strained left hamstring, Boggs scored without having to slide when Bernie Williams hit a double into the left-center-field gap to tie the score, 1-1.

The Yankees did not enjoy the new game very long as Tino Martinez's run-scoring single in the sixth put Seattle ahead, 2-1. By JACK CURRY

Copyright 1995 N.Y. Times News Service