BOSTON -- If abbreviated outings by the starting pitchers have become too much of a recurring theme for the Red Sox in recent weeks, two other themes have allowed the club to remain in first place in the American League East as June winds down to just one more day.

The offense keeps bashing the baseball around and the bullpen continues to get the job done far more often than not.

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It was that formula that allowed the Red Sox to upend the Royals, 7-6, on another hot and steamy night at Fenway Park on Tuesday.

“We're putting together good at-bats. The line is moving, we're walking too, we've been controlling the strike zone,” said Red Sox manager Alex Cora. “We're doing a lot of good things offensively.”

And the bullpen almost always makes that offense stand up -- particularly of late.

Sox relievers have not allowed an earned run in the last three games, covering 11 innings. They’ve posted a 0.51 ERA (one earned run in 17 2/3 innings) in the first five games of this seven-game homestand and have a 1.16 ERA in the last eight games.

“The bullpen has been throwing the ball really well. I think for the vast majority of the season the bullpen has been really, really solid,” said closer Matt Barnes, who locked down his 18th save. “Guys are feeding off of each other, guys are doing their thing, wanting the ball, competing and going out there and doing their job in big situations. It’s been awesome, it really has.”

Their winning streak at five games, the 49-31 Sox have opened up a two-game lead in the AL East. The season will be half over on Wednesday night and Boston has positioned itself for a potentially thrilling stretch run.

Thus far this month, the Sox are 17-10. This, even though the starting pitchers have gone less than five innings in 10 of the last 21 games.

Nick Pivetta was the starter who didn’t go as long as the Sox hoped on Tuesday, lasting just 4 1/3 innings while giving up nine hits -- including three homers -- and six runs.

“I’m definitely not satisfied with it,” said Pivetta, who fired 6 2/3 no-hit innings in his previous start before getting taken out. “I think I really have to bounce back from this one. I need to go deeper in the ballgame. I need to give more innings so I can give the bullpen a little bit more of a rest there. But at the end of the day, the bullpen picked me up, the hitters picked me up all game and we came out with the win, so I think that’s really important.”

Once Pivetta departed, the Royals stopped scoring.

Relievers Yacksel Ríos, Darwinzon Hernandez, Adam Ottavino and Barnes combined for the final 14 outs, allowing four hits and one walk while striking out six.

It was the MLB-leading 27th comeback win for the Red Sox. Prior to the game, Cora was asked if he would prefer to have some less stressful games in which his team could play from ahead.

“For my heart and our bullpen,” said Cora.

But with the offense once again at its relentless best, overcoming three deficits, Cora had Barnes pitch for the third straight day while Ottavino pitched for the second consecutive day.

“They were really good, starting with Ríos and Darwinzon,” Cora said. “It's just one of those, they're throwing the ball well. I know at the end we went to Adam and Barnesy [again], but just what the offense did today, they deserved for us to actually use them in that spot. We've been using them a lot. Maybe they'll be out tomorrow. Maybe it rains tomorrow. We were aggressive with them, we finished the game, and now we move on to tomorrow.”

Meanwhile, the offense seems to have no issue helping to carry the day again and again.

The biggest swing of Tuesday’s game was from J.D. Martinez, who rifled a two-run double down the line in right in the bottom of the sixth that scored Alex Verdugo from first. That gave Boston the lead it never relinquished after several swings of momentum earlier in the game. It was part of a four-RBI night for Martinez.

“I think we’re doing a really good job of really staying convicted on our approaches and not chasing around the zone,” said Martinez. “We’re making these guys work and just putting the ball in play hard when we get the mistakes and the pitches we’re looking for.”

At this point, it seems clear that overlooking the Red Sox would be a mistake. Other than the Giants, no team in MLB has exceeded the expectations of so many -- at least of the external variety.

“I know last year was [tough], I’ve always believed in our offense,” said Martinez. “Last year we struggled a little bit to pitch and these guys have been great this year. I’m a believer that if you have good pitching, the offense always finds a way to step up.”