Jon Lester

Jon Lester may not be even close to the All-Star form everyone expected him to be going into 2012, but game-by-game, slowly but surely, the struggling lefty is improving.

Unfortunately, his latest performance was again not good enough as the Red Sox fell to the Twins, 5-0, to open their four-game series at Fenway Park on Thursday night.

Lester tossed eight innings – the first time he’s done so since pitching a complete game on May 14 – and his pitching line was encouraging. He struck out seven, didn’t walk anyone – for the first time since June 27 – and didn’t give up a home run either, the first time he’s done that since the Red Sox returned from the All-Star break.

While Lester may have pitched well enough to win, his counterpart was even better. Samuel Deduno, in just his fifth big-league start, kept the Red Sox scratching their heads time after time Thursday night. The 29-year-old righty allowed only two hits in a six-inning shutout to take the victory, despite walking four and striking out just one.

Here’s what went right and wrong for the Red Sox as they fell for the second straight time to fall back to a .500 record:

WHAT WENT RIGHT FOR THE RED SOX

• Lester’s cutter was working early and sharp in the first inning, helping him to retire the side in order. He struck out both Denard Span and Ben Revere looking via the cutter before forcing Josh Willingham into a fly out to center.

Lester’s 12 pitches in the first inning was the least he’s thrown since June 16 against the Cubs, when he threw only seven.

• Adrian Gonzalez was the offense for the Red Sox on Thursday night, as he notched the team’s only two hits as he went 2-for-2 with a walk. His stand-up double in the fourth put him in sixth among American League leaders with 29 doubles this season, and he has now hit safely in 32 of 37 games since June 20.

• After giving up a leadoff double to Brian Dozier in the fifth, Lester battled back to escape trouble, retiring the three next batters via groundout, the last two of which were with Dozier 90 feet away at third base.

• Lester gave up an RBI double in the sixth that put the Twins up 3-0, but responded like the vintage Lester. He didn’t allow a base runner for the rest of the game as he retired the final seven batters he faced before exiting in the eighth.

WHAT WENT WRONG FOR THE RED SOX

• Lester’s third inning could have been made much worse if it weren’t for impressive defensive plays from both Gonzalez and Ryan Kalish.

After retiring the first six batters in order through the first two innings, Lester gave up two runs on three hits in the third. Both runs came with two outs after Gonzalez made a nice pick on a diving stop at first. After the runs scored, Willingham hit a high, mischievous fly ball to short-center that Dustin Pedroia couldn’t get to as Kalish raced in for the diving grab, saving the Sox from an embarrassing gaffe.

• The Red Sox couldn’t buy a hit in the opening innings as they waited until the fourth to register their first one. Between the second and third innings, Deduno forced the Red Sox into six consecutive groundouts.

• The Red Sox only put on six base runners the entire game, and failed to convert on any threat. They had two runners on base at three different occasions, but each threat ended in a fly out.

• Will Middlebrooks ended his hitting streak at nine games. The third baseman went 0-for-3 with a strikeout.

• Dozier capped the scoring with a two-run homer off Alfredo Aceves in the ninth inning.