BOSTON -- Long before the comeback and then the early-morning letdown, another recurring theme developed for the Red Sox, and it’s not a good one.

Nathan Eovaldi again couldn’t settle into a groove.

The hard-throwing righty was touched up for seven hits and five runs over four innings against the Giants, walking three and striking out six. Boston wound up losing the game, 7-6, in 15 innings at Fenway Park.

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In six starts since moving back to the rotation, Eovaldi has a 6.85 ERA. Somehow, he hasn’t earned a decision in any of those starts. With Eovaldi signed for another three seasons, his drop-off in performance is cause for concern.

The Eovaldi who dazzled for the Red Sox in the rotation and bullpen last October hasn’t appeared very often this season.

“A lot of pitches in the middle of the zone and then a lot of walks,” said Red Sox manager Alex Cora. “There were a few hits in on 1-2 pitches down in the zone. The split wasn’t great. It’s one that he has two more starts and the hope is for him to keep getting better and finish on a positive note going into the offseason.”

Eovaldi, who had elbow surgery in April and then biceps tendinitis that delayed his return until July, is adamant there are no physical issues. But he is caught in between with his pitch selection and isn’t locating well.

“Physically I felt fine. My fastball felt like it was coming out really well. I’ve got to use more splitters,” Eovaldi said. “I felt like I threw the curveball well. The cutter was a little inconsistent. I wasn’t throwing too many for strikes but they were just able to make the hits fall in.”

The way Cora looks at it, Eovaldi’s biggest issue is not using the upper portion of the strike zone to put hitters away like he did down the stretch last season.

“Last year we talked about it: This guy, with his stuff, we need him,” said Cora. “We have to get him to pitch up in the zone again. He can get some swings and misses up there, some weak contact. From there, we can expand down with the breaking ball and the split.”

The final run Eovaldi allowed on Tuesday night at Fenway Park was a dramatic one -- struck by Mike Yastrzemski, who was playing his first game at Fenway Park, where his grandfather Carl was a legend during a 23-year career.

Cora: Loss symbolized season

To Cora, the frustrating defeat and the highs and lows of a game that took five hours and 54 minutes perfectly encapsulated his team’s inconsistent season.

“If you can [sum up] our season in six hours, it was right there, honestly,” Cora said. “Close games, we didn’t hit with men in scoring position. We didn’t pitch well in the beginning but then we pitched well [later]. We played good defense but then we didn’t.

“Long game, extra-inning games, using the bullpen knowing we have a bullpen day maybe tomorrow, it’s been like that the whole season. That’s how I felt.”

The Red Sox and Giants combined to use 24 pitchers, tying an MLB record for a single game, and Boston left 17 runners on base.

With 12 games left, the Sox trail the Rays by nine games for the second Wild Card spot. Their magic number for getting eliminated is now three.