Jon LesterBOSTON — After three big steps forward, Jon Lester took one giant leap backward Friday.

Lester, who had found a rhythm in his previous three starts, struggled mightily against the Diamondbacks in Friday’s series opener. He allowed six runs on 11 hits and failed to get through the fifth inning as Arizona won, 7-6.

Simply put, Lester was knocked around.

“I’ll take my beatings if they find holes in the infield. I’ll tip my hat all day to that. But when you’re giving up doubles in the gap and balls off the wall and misfired fastballs, it’s unacceptable,” Lester said. “Like I said, I’ve got to find a way to make that adjustment and I didn’t do that.”

The adjustment that Lester is referring to is his pitch location, which was an issue throughout Friday’s contest. Lester tossed seven shutout innings in his last start in Baltimore on Sunday, and a big reason was his ability to keep the ball down. The story was much different Friday, though, as the Diamondbacks hammered a number of pitches that were left up in the zone.

“You make adjustments, but if you don’t get the ball down, it doesn’t matter,” Lester said. “The fastball was up, the cutter was up, everything, the changeup was up. The adjustments don’t matter if you don’t get the ball down in the zone. I mean there’s obviously a lot of fly balls hit tonight that the past three or four starts hadn’t been the case. I’ve been keeping the ball on the ground, and like I said, the ball was just elevated and that’s what they do when you elevate.”

Lester lasted into the seventh inning in each of his previous three straight starts, but Friday’s effort was his shortest of the season. He lasted just 4 1/3 innings against the D-Backs, and he exited with the Red Sox trailing 6-4. Boston eventually tied the game when Stephen Drew knocked a two-out, two-run homer into the bullpen in the sixth inning, but Lester’s poor outing put the Sox into a difficult spot.

“It was inconsistent location within the strike zone,” manager John Farrell said. “He didn’t create any additional issues by issuing any walks, and it was more him trying to go away from some right-handers that he pulled the ball back toward the middle of the plate or inner-third to [Cody] Ross, to [Martin] Prado. Not as sharp to his arm side as he’s been his last couple of times out.”

It’s now back to the drawing board for Lester, whose season has been a combination of highs and lows. The left-hander doesn’t think he’s too far off, though, as he struck out six and didn’t walk anybody despite being knocked around Friday.

“It’s not like I have to reinvent any type of wheel or come out and start throwing right-handed or anything,” Lester said. “It’s pretty simple, keep the ball down and if I do that, it’s a different story than tonight. When I was able to do that, I got some swing and misses [and] got some bad contact. But I wasn’t able to do it consistently tonight and they did a good job of hitting those mistakes, making me work, a lot of foul balls. Like I said, the ball was just up and you got to find away to get the ball down and get deep into the game.”

Lester will continue to be an integral part of the Red Sox’ 2013 rotation, and Boston’s hope is that he’ll soon return to being a consistent starter. But getting to the intended destination is difficult when you backtrack every now and then.

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