Both teams flip-flopped the lead in the final frame, ending when right fielder Shin-Soo Choo hit a three-run blast to give the Indians their sixth walk-off win via the long ball this season.
Choo missed Monday's game as his wife gave birth to their first daughter. He came straight from the hospital to Progressive Field less than two hours before Tuesday's first pitch.
"We didn't even know if he was going to make it for the game," said Indians manager Manny Acta. "I'm glad he came."
"That's the best present, right?" said Choo, who played briefly for the Mariners from 2005-06 before being traded to the Indians. "It was for my daughter and my wife. I think that's my first walk-off homer in my baseball career. It feels great."
The loss went to Mariners closer Brandon League, who gave up a leadoff double to Ezequiel Carrera, then saw second baseman Dustin Ackley throw high to third on a fielder's-choice grounder by Asdrubal Cabrera to set the table for Choo.
"I came with my fastball and you saw what happened -- it was flat today," said League, who suffered his second walk-off loss in three save opportunities in Cleveland this season. "I just have to go back to the drawing board and make it sink."
Seattle had taken a 5-4 lead in the top of the ninth off Cleveland closer Chris Perez on a two-run double by rookie Trayvon Robinson, but League couldn't hold on this time after getting his 31st save the night before.
"He's been fantastic," manager Eric Wedge said. "You're going to have games like that. You're not going to be perfect. We felt like we did a good job against their guy and they did a good job against our guy. And they had the last at-bat."
Robinson went 2-for-4 with a pair of doubles, two RBIs and a run scored, and appeared headed for hero status with his full-count shot off Perez. But 14 games into his Major League career, the youngster was ready to deal with that roller coaster.
"It's part of the game," he said. "Live and learn. Turn the chapter. Just keep going."
Two hours earlier, the rumblings of an East Coast-based earthquake kept going for more than a minute, though players on both teams were unaware of the situation on the field.
Though the press box and upper deck of the stadium swayed noticeably for more than a minute during a Choo at-bat in the third inning, play never paused and neither did the Indians, as they rallied late for their fifth win in six games against Seattle this season.
Playing a makeup game from a mid-May rainout in the same city where they had four games snowed out in 2007, the Mariners ignored the latest grumblings from Mother Nature, but they couldn't overcome a Cleveland offense that knocked out seven extra-base hits.
Cortes had two outs and two men on when he was lifted after hurting his ankle while coming down wrong on a delivery. Wright then gave up Santana's single, though right fielder Casper Wells got him out of further trouble by gunning down Choo as he tried to take third.
Manager Eric Wedge started six rookies in the contest, including pitcher Blake Beavan, who bounced back from a pair of rocky outings to give Seattle six solid innings before turning a 3-3 tie over to the bullpen.
Beavan allowed eight hits, but walked just one and limited damage to single runs in the first, fourth and sixth innings. His record remains 3-4 -- with a 4.14 ERA -- and he recorded his seventh quality start in nine outings.
"He was a little better," said Wedge. "He did a better job with his fastball. I'd still like to see better command of his fastball, which is what he does. But he did a good job against a pretty good lineup today."
After Beavan fell behind 1-0 with a 26-pitch first inning, Seattle scored in the second as Adam Kennedy doubled and scored on a single to left by Miguel Olivo, increasing his team-leading RBI total to 51.
The Mariners took the lead with two more runs in the fifth on three straight hits, including doubles by Robinson and Franklin Gutierrez. Ichiro also had an RBI single in that frame.
But in the end, the Indians had the last shot and made the most of it against League, who was also beaten by a three-run home run in Progressive Field on May 13 by Travis Hafner.
"I've faced him before," said Choo. "He throws a good hard sinker. So with nobody out and runners on first and third, I tried to hit the ball hard somewhere. I tried quick swings, to start early and let good things happen."
But League and the Mariners didn't have much time to stew over this one.
"Last night was a weird game," said League. "Today was back and forth again. Now we've got another game in three hours. We'll see how that one plays out."
( COURTSEY OF www.seattle.mariners.mlb.com)