BOSTON -- Tuesday should have been a night for the Red Sox to laud Martín Pérez for his third consecutive solid start.

The lefty, thrust into a difficult position of being the team's No. 2 starter when he was acquired to hold down the fifth spot, allowed two runs on three hits over 5 2/3 innings, walking two and striking out five.

Instead, Pérez (2-2, 3.38 ERA) became a footnote on a night the Red Sox unraveled in the top of the seventh, allowing six runs in an 8-2 loss.

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Keep in mind that the Sox trailed just 2-1 when that inning started. By the time the seventh-inning stretch rolled around, it was 8-1.

Early on, the Boston offense, as it has on too many occasions this season, sputtered, costing Pérez any chance of winning on a night he was good enough. If the Red Sox had finished strong and won the game, there would have been more talk about Perez's strong changeup -- which generated seven whiffs in 32 pitches and was a weapon throughout the performance.

"I gave my team a chance to win the game," Pérez said. "I think the relievers just got behind sometimes, a lot of walks, and I think we have to throw more strikes to the hitters. That happens. It's a crazy game."

In that seventh inning, a combination of shaky relief pitching by Austin Brice and a couple of defensive letdowns added up to spell doom.

"We played a really good game for six innings. We didn't swing it again, but it was a good ballgame until then," said Red Sox manager Ron Roenicke. "Brice has been pitching great for us, he just didn't have his command today -- and that happens. It's a shame, as good as he's pitched for us, that he ends up giving up that many runs. But it's just one of those games where he just didn't have it. And then trying to close it bringing in the two guys we did, it turned into a bad game."

This is the way it's going for a last-place team that is now 6-11 and five games back in the American League East.

There have been slight bursts, such as when they won two in a row at Citi Field against the Mets. More recently, they scored three victories in four games, capped by a walk-off homer by Mitch Moreland against the Blue Jays on Sunday. The Red Sox have simply been unable to sustain any momentum.

While pitching was the obvious question coming into the season, the breakdowns have been well-divided between each facet of the team.

"It certainly is right now, and when you're going bad, that's how it goes," said Roenicke. "You just don't seem to click on both sides or your defense lets you down or something happens. But we've got to figure this out."

If Tampa Bay tormenting the Red Sox in Boston feels familiar, it should. Going back to last season, the Rays have taken 11 of their last 12 games at Fenway, including the last six in a row.

"It's hard to figure out, but they've got outstanding pitching," said Roenicke. "I know we're not hitting, but that's part of the reason, because their pitching is really good. They bring arms out of the bullpen, and they not only have velocity, but they have great off-speed stuff. So you're probably not going to score a lot of runs against them, and we know that we have to shut down their offense."

Roenicke sounded a little envious about the collection of arms the Rays boast, and you can't blame him.

Brice simply fell apart in the seventh, getting just one out while allowing four hits and five runs.

It wasn't all his fault. On a grounder down the left-field line by Manuel Margot, Andrew Benintendi couldn't cut the ball off before it banged against the garage door on the side-wall, allowing Willy Adames to score all the way from first.

There was a chopper up the middle in which second baseman Michael Chavis forced a throw to the plate when he had no play, instead of taking a likely out at first against the slow-footed Yandy Díaz.

Though the miscue by Chavis simply turned a 4-1 deficit into a 5-1 hole, the infielder, who turned 25 on Tuesday, took it hard.

"When I had to jump for it, it just took my momentum and then I had to do a jump throw, which is where it got messed up. I should have decided to go to first base at that point," Chavis said. "That's on me. Pretty much lost the game for us, honestly. That's pretty tough. It kind of just took the wind out of us."

Another run crossed home in the nightmarish inning on a passed ball by catcher Christian Vázquez. In the eighth, with the Red Sox finally generating a rally, Benintendi tripped going from first to third, costing his team a precious out.

"We've been struggling a little bit," Pérez said. "We still have [43] games. Like I said, turn the page and put all the pieces together to find a way to win."

With the Rays coming to town and taking care of business in the first two games of a four-game series, the Red Sox will need to figure out a way to beat former Cy Young Award winner Blake Snell on Wednesday to have a chance at splitting the series.