Cody Ross and the Red Sox had a rough night on Wednesday. (AP)

Adrian Gonzalez defines himself as a run producer. That being the case, though he has struggled at the plate this year, he had been able to hang his hat on the fact that he still had found a way to succeed in the game’s most meaningful situations. Prior to Wednesday, he was hitting .438 with a 1.234 OPS with runners in scoring position.

But given a chance to impact Wednesday’s contest, he failed in crucial situations. With two outs, the bases loaded and the Sox trailing, 4-1, Gonzalez struck out swinging at an 84 mph slider from reliever Ryan Cook, and in an uncharacteristic show of frustration, he punched his bat to the ground after smothering the biggest Red Sox rally of the night in an eventual 4-2 loss to the A’s.

He had one more shot in the ninth, representing the tying run with two outs, but he grounded out to short to end the contest.

Gonzalez is now 0-for-15 with three walks in his last four games, matching his longest stretch of hitless games since he came to the Red Sox. He is 0-for-17 dating back to Saturday’s contest, his longest streak of hitless at-bats as a member of the Sox.

The likelihood is that Gonzalez will snap out of his funk, but for now, that appears to be little consolation to a player accustomed to playing at an MVP-caliber level as he dipped to a .250 average and .697 OPS.

WHAT WENT WRONG FOR THE RED SOX

– Daniel Bard lacked the swing-and-miss stuff that he had featured in his first three starts. He came into the game having punched out 19 batters in 18 2/3 innings, but on Wednesday, he elicited just four swings and misses (two on fastballs, two on sliders). On a cold night similar to the one in which he dominated the White Sox last Friday, Bard’s stuff seemed to flatten as the game progressed. While he was victimized in part by a misplay of a catchable ball close to the Green Monster, in his final inning, he threw 23 pitches without a single swing-and-miss, and the A’s seemed like they were teeing off on a fastball that still registered at 93-94 mph but with diminished movement.

Bard had given up just one run on four hits over five innings entering the frame. But in the sixth, he permitted three more runs on four more hits (three doubles) while hitting a batter.

– Gonzalez is struggling simply to put the ball in play. In five plate appearances, he did so just twice, going 0-for-3 with a pair of strikeouts and a walk. He is spraying foul balls down the left field line with uncommon frequency.

– Cody Ross continued to struggle with the Green Monster, badly misplaying a fly ball down the left field line at the start of the sixth inning that helped set in motion a three-run Athletics rally that ultimately proved the difference in the game. He also went 0-for-4 with a strikeout at the dish.

WHAT WENT RIGHT FOR THE RED SOX

– Will Middlebrooks got a number of firsts out of the way, including several of the unexpected variety. Though he has always been an aggressive hitter with relatively low walks totals, his first plate appearance netted his first career walk, as he took four straight balls from Brandon McCarthy. He immediately stole second for his first career bag. Then, in his second plate appearance, Middlebrooks topped an 81 mph curveball, with the slow chopper to third netting him an infield hit for his first big league knock and a souvenir baseball.

More true to his signature style of play was his next plate appearance in the seventh, when Middlebrooks ripped a cutter away down the right-field line for a double. Middlebrooks has said that he likes to identify pitches middle-away that he can drive to the opposite field. In his final at-bat of the night, he did notch his first professional out, punching out on a 95 mph fastball by Ryan Cook.

– Ryan Sweeney ripped a one-out double to right in the bottom of the first inning, his major league-leading 12th double of the year.

– Clayton Mortensen recovered from a leadoff single and wild pitch to deliver a solid shutout inning in his Red Sox big league debut, striking out a pair of batters (Josh Reddick on a slider, Yoenis Cespedes on a changeup) and getting a groundball out. He then came back out for a 1-2-3 eighth inning in which he punched out two more batters, freezing a righty on a fastball and getting a lefty on a slider. Finally, he punched out two more in the ninth, again showing a swing-and-miss changeup and slider. His six strikeouts (in just three innings) were just one shy of his career high of seven, achieved as a starter for the A’s in 2010.

The right-hander, acquired from the Rockies in the Marco Scutaro deal, said this spring that he hoped to prove that he is “not a schmuck.” With Wednesday’s outing, he took a significant step towards such a demonstration.

Though Mortensen will likely be sent back to Pawtucket when Aaron Cook is called up, the Red Sox appear to be planning to insert him into the Triple-A rotation to lengthen him out given his early-season success in Pawtucket, where he has a 0.90 ERA, 10 strikeouts and four walks in 10 innings. He has put himself on the radar as a relevant depth option for the Sox rotation and bullpen.