BOSTON -- What was supposed to be a night off for Mike Lowell instead turned into a power-packed performance -- one that led the Red Sox to an emotion-filled, 7-5 victory over the Tigers on Tuesday at Fenway Park.

Lowell's opportunity was created by, of all things, a benches-clearing altercation. Kevin Youkilis, after being hit by a Rick Porcello fastball in the bottom of the second inning, charged the mound and was ejected.

Up stepped Lowell, who took over the No. 4 spot in the batting order and promptly clubbed two home runs. The first was a solo shot to left in the third inning that snapped a 3-3 tie. Two innings later, Lowell hit a towering two-run blast over the Green Monster in left-center to make it 6-3.

"Yeah, it was kind of crazy," said Lowell. "Emotions ran a little high there. It feels great. I think I still do things even though I'm not playing that day to get myself ready in case I need to go in the game, and I think the situation we have now is kind of unique and kind of weird. I just try to get myself ready."

Since the July 31 trade that brought Victor Martinez's big bat to the Red Sox, manager Terry Francona has used a rotation system that has left Lowell on the bench more than he's accustomed to. Though the veteran isn't a big fan of sitting, particularly when he's been swinging the bat as well as he has of late, Lowell hasn't let the arrangement affect his performance.

"When you're swinging the bat well, I think you want to play every day. I'll stand by that," said Lowell, who is hitting .368 since the All-Star break.

Both home runs came against Chris Lambert, who was only in the game because Porcello was also ejected after his grapple with Youkilis. Lowell became the first Boston player since Joe Foy on June 9, 1967, to belt two home runs off the bench.

That was just one of several storylines on an eventful night. Making his first Major League start, Red Sox right-hander Junichi Tazawa earned his first career win, giving up four hits and three runs -- one earned -- over five innings. He walked two and struck out six, throwing 98 pitches. It was a nice rebound for Tazawa, who gave up a walk-off home run to Alex Rodriguez in the 15th inning in his Major League debut Friday.

The 23-year-old Tazawa (1-1) never pitched professional baseball before this season. The Red Sox (64-48) signed him last December out of the Industrial League in Japan, and he spent most of this season at Double-A Portland. When the Red Sox designated the struggling John Smoltz for assignment last week, Tazawa got the call.

"In the past few days, everything has happened all of a sudden," Tazawa said. "I didn't expect to be in the Major Leagues and I didn't expect it to happen so quickly. Things have just been happening very fast for me. I didn't think I would get the win today, and I'm very happy that I did."

The Red Sox were quite happy as well. After losing six in a row, they've rebounded to win the first two of this four-game series with the Tigers (59-53). The Sox remain 5 1/2 back in the American League East but increased their lead over the Rangers to 1 1/2 games in the Wild Card standings.

Tazawa had a rocky first, loading the bases with one out. But it looked like he had made the pitch to get out of it when Carlos Guillen hit a grounder to shortstop that looked primed to be a double play. But Nick Green's feed to Dustin Pedroia was off the mark, and everybody was safe to make it 1-0. Magglio Ordonez got another run home on a fielder's choice grounder to Green. Brandon Inge punched an RBI single to left, putting the Red Sox in a 3-0 hole before they took a swing.

"Under the circumstances, I thought he was exceptional," said Francona. "The first inning, he did a lot of things in our power to make it a tough inning and he kept his poise -- he never wavered."

Tigers star Miguel Cabrera, who was hit on the left hand by a pitch in the first, had to leave the game with two outs in the second when he felt discomfort after a foul ball. Cabrera was hit by Brad Penny in the fourth inning of Monday's game.

It didn't take long for tempers to flare after Cabrera's exit from the game. Porcello drilled Youkilis in the back with his first pitch in the bottom of the third. Without hesitation, Youkilis charged the mound and threw his helmet toward Porcello. The two players then tangled with each other, with Porcello landing on top of Youkilis when they hit the ground.

Youkilis was also drilled in the fourth inning of Monday's game by Tigers right-hander Edwin Jackson.

"A ball came up high at my numbers and it looked like there was intent there, with two days in a row of getting hit," said Youkilis. "At some point, you have to do something to protect yourself as a hitter. I had enough of it, I felt like I had to do what I had to do."

As soon as play resumed, the Red Sox got to Lambert (0-1). David Ortiz ripped a single and Jason Bay followed by unloading for a game-tying, three-run homer to left.

It was Bay's third homer in his past four games, a good sign for a man who was in a deep slump for six weeks.

"It's been a constant battle," said Bay. "When I was going well, I was quick to point out that it could be worse, and it got a lot worse. It's nice to feel better again and contribute the way I can. It's nice to feel 'normal' again. It's only been a couple days, but it's been a nice turnaround for me."

Did the altercation inspire the Red Sox? Perhaps.

"Sometimes you need those kinds of things and it will get you going," said Martinez.

Or maybe it was just a matter of circumstance. After all, the entrance of Lowell's hot bat was a game-changer.

"He starts out sitting there watching, and pretty quickly he's down there stretching and having a huge [bearing on the] outcome in the game," said Francona. "I do think that shows a lot of professionalism. That's not an easy thing to do, but he comes in and directly impacts the game twice. It's good for us."

What's good for Lowell is that he will be back in the lineup on Wednesday night. How much he will be in there going forward is unclear.

"I take it as what it is, but I'm trying to make their decision as tough as possible, that's for sure," said Lowell. "I have to at least feel good that I'm swinging a good bat. I don't know why you wouldn't want good bats in your lineup."