The Mariners surrendered a two-run lead in the eighth inning, took another two-run lead in the 11th inning and gave half of that back before they pulled out a 7-6 victory before 38,078 -- their 20th one-run win of the season.
Mark Lowe, pressed into closer duties because David Aardsma has a bit of sore back and an often-used right arm that needs an occasional breather, got three outs before the Red Sox could score the two runs they needed to compensate for the clutch two-run double Mariners catcher Rob Johnson hit in the top of the 11th.
Lowe, who pitched two innings in Thursday night's 8-4 win over the Yankees, retired the first two batters in the bottom of the 11th before surrendering a solo home run to rookie George Kottaras and a single to J.D. Drew.
The last pitch he threw to Dustin Pedroia, the reigning American League Most Valuable Player, was hit to third baseman Chris Woodward. His clean pickup and throw to second baseman Jose Lopez sealed Seattle's 41st win of the season.
"It's fun, because these guys just don't give up," manager Don Wakamatsu said. "There's never a feeling of discouragement in the dugout. There's just a strong belief system in each other, and it's great to be a part of that."
Johnson stepped into the spotlight with his first career three-double game, tying a club record.
The first two, off Red Sox knuckleball specialist and 10-game winner Tim Wakefield, went to left field. The third one went the opposite way -- over first baseman Mark Kotsay's head, easily scoring Franklin Gutierrez and Ryan Langerhans.
Gutierrez walked and Langerhans walked to start the inning and then advanced on Chris Woodward's sacrifice bunt.
"I've never faced [Red Sox reliever Ramon Ramirez] before, but I knew they were going to throw me offspeed pitches, so I concentrated on keeping my hands back," Johnson said. "I'm really happy I took the first pitch, because it gave me a chance to see how much his offspeed pitch breaks."
The final pitch was a breaking ball that was up and away. Johnson went with it and drove it to right.
As the series opener bobbed and weaved through the early and middle innings, Wakefield and Mariners starter Felix Hernandez, named earlier in the day as the American League Pitcher of the Month for June, battled it out.
Hernandez went into the game with a 2-0 record and an 0.00 ERA at Fenway in 15 innings.
The Red Sox came out swinging and scored two runs in the first inning.
"All I had was a fastball," Hernandez said. "I couldn't get a good feel of my breaking pitches until the second inning, and they have a really good lineup. I was behind in the count a lot. It was tough."
Even so, he departed after the seventh inning with a 4-3 lead.
"He was dead tired after seven innings," Wakamatsu said, "and he had to come out of there."
The suddenly struggling Sean White was the first to get a shot at protecting the two-run lead that Lopez provided with a solo home run
in the top of the eighth.
A one-out walk to Jason Bay and an ensuing single by Kotsay put the tying runs on base, prompting Wakamatsu to do something he preferred not to do.
Only a few hours after being activated from the 15-day disabled list, which actually kept him sidelined for 52 games, Kelley was asked to protect the lead.
He retired the first batter he faced on a fly ball to left fielder Langerhans, who caught the ball a few feet in front of the Green Monster.
But the next batter, Nick Green, hit a game-tying double off the wall.
Wakamatsu said prior to the game that he wanted to get Kelley in a few "non-pressure" innings before throwing him back into a high-stress, late-inning role.
"I thought he looked sharp," the manager said. "He left one pitch up, and that's a 320-foot fly ball that scored two runs."
Kelley agreed, saying, "It wasn't that bad of a pitch. I was surprised. I thought it was a routine fly ball."
As for being thrown right back into the frying pan, the rookie said, "That's the way I would like it. When we have a lead, I want to put it all on me."
Kelley regrouped and retired the next batter, Kotsay, stranding the go-ahead run at second.
Right-hander Chris Jakubauskas pitched two scoreless innings to get the win and even his record at 5-5, while Lowe notched his first save of the season.
"I always think we are going to win until we don't," Red Sox manager Terry Francona said. "We put ourselves in a little bit of a hole, but I think that's the general feeling all the time. There's no reason to stop playing until we run out of outs."
Across the way, in the other clubhouse, basically the same thing was being said.