Wei-Yin Chen pitches seven scoreless innings for the win. (Mitchell Layton/Getty Images)

Winning a series against the division rival Boston Red Sox, especially at home, especially when the defending World Champions are struggling, has to be considered somewhat significant for the Orioles — even in June.

What adds to the accomplishment, though, is how these struggling-for-an-identity Orioles did it: with excellent starting pitching.

It’s nutty, but true.

In the Orioles’ 6-0, soggy victory Wednesday night, Wei-Yin Chen became the third consecutive Orioles starter to go at least six innings and allow one run or fewer. Boston scored just one run total in three games this week at Camden Yards — with Baltimore winning two and losing the other, 1-0.

It’s the first time the Orioles have allowed one total run or fewer over a three-game span since Aug. 4-6, 2012, and the first time they’ve done it at home in a three-game series since Kevin Brown, Ben McDonald and Mike Mussina registered shutouts of the Detroit Tigers on Sept. 29 to Oct. 1, 1995.

The Orioles hadn’t limited the Red Sox offense in such a manner in a three-game series since Sept. 2-4, 1974, when Ross Grimsley, Mike Cuellar and Jim Palmer threw consecutive, complete game shutouts — 1-0, 1-0 and 6-0.

Throw Bud Norris (eight shutout innings), Chris Tillman (one run in six innings) and Wei-Yin Chen (seven scoreless innings) into that vaunted company. Not bad for a starting rotation that began Wednesday 11th in the American League in ERA with a combined 4.46 mark.

And certainly surprising considering in the last game before the Boston series, Orioles’ starter Ubaldo Jimenez gave up six earned runs in just 21 / 3 innings in an 11-1 loss to Oakland.

Wednesday’s win marked the first time in 2014 that the Orioles (33-31) have captured a rubber match at home in five tries; they’re just 3-7 total in those situations this season. It also put the second-place Orioles 4 ½ games behind the AL East-leading Toronto Blue Jays, who come to Camden Yards on Thursday to start a four-game series.

The fourth-place Red Sox (29-36) have lost seven of nine.

By the time Wednesday’s 1 hour 38-minute rain delay had ended and play resumed in the bottom of the seventh just before 11 p.m., only a fraction of the announced crowd of 25,886 remained. Most congregated in the first five rows between the foul poles, and their reactions resonated throughout the near empty stadium — giving the last two innings the feel of a high school game.

Although he wasn’t around at the end, Chen (7-2) was the primary reason for Wednesday’s victory, the club’s fifth in 10 games against the Red Sox this season.

He was in control from the beginning, retiring the first 11 batters he faced before Dustin Pedroia ended the Taiwanese lefty’s bid for a perfect game with two outs in the fourth.

Pedroia, who entered the night batting .500 (12-for-24) against Chen lifetime, hit a liner that bounced just before the warning track in right. Nick Markakis grabbed the carom off the wall and threw perfectly to shortstop J.J. Hardy, who tagged a sliding Pedroia at second.

That was the Orioles’ 12th outfield assist this season and a team-leading fourth by Markakis.

Chen kept rolling after that.

He faced the minimum number of hitters — 15 — through five, and didn’t allow two base runners in the same inning until the sixth. He quickly wiped out that threat with one of his three, inning-ending double plays.

How good was Chen, who has won four straight decisions and hasn’t lost since May 3?

He didn’t walk a batter, hit one and allowed three balls in an at-bat just three times. Chen had mastery of all his pitches, and was precisely locating his 93-mph fastball while getting a lot of movement on his slider and curveball — helping him collect a season-high seven strikeouts while yielding four hits.

He threw 56 of his 87 pitches for strikes and tied his season-high for innings with seven — and likely would have pitched longer if it hadn’t been for the steady rainstorm that stopped action in the middle of the seventh.

About the time John Denver’s “Thank God, I’m A Country Boy” ended in the seven-inning stretch, the umpire crew signaled for a delay.

The Red Sox attempted a rally in the eighth when J.J. Hardy made his seventh error of the season — and sixth in seven games — on a throw that got past first baseman Chris Davis. Boston thought Mike Napoli should be awarded second base due to fan interference, but replays showed the throw would not have gone into the stands even if it hadn’t touched the Orioles fan in the first row.

Darren O’Day picked up the final two outs on a comebacker and a drag bunt in the eighth and Zach Britton preserved Chen’s shutout with a perfect ninth.

The Orioles’ offense did enough against Boston right-hander Rubby De La Rosa (1-2) to get Chen the win.

After scoring just five runs total in their past three games, the Orioles plated three in the first inning Wednesday.

Steve Pearce drew a one-out walk and Adam Jones followed with a double into the left field corner to score a hustling Pearce from first.

Two batters later, Davis slammed an 86 mph change-up into the right field seats to give the Orioles a 3-0 lead. Davis, who led the majors with 53 homers in 2013, now has 10 this season, including three in his last eight games.

The Orioles scored again in the fourth on a RBI single by Nick Hundley that scored Hardy. They nearly went up 5-0 in the fourth when Markakis hit a sharp, two-out grounder that Xander Bogaerts grabbed on a dive and then flipped to second.

Initially, Hundley was ruled safe — allowing Jonathan Schoop to score. But Boston Manager John Farrell challenged the ruling on the field. After a 1 minute 58-second review, the call was overturned and the inning ended.

The score remained 4-0 and Markakis remained in eighth place on the franchise’s all-time hits list. He is one behind former teammate Brian Roberts for seventh.

The Orioles padded their lead in the eighth on bases-loaded walks to Schoop and Markakis by Boston reliever Chris Capuano.

Markakis will look to move up the hits list this week against the Blue Jays (39-28) in a matchup of two teams that were supposed to be in the bottom of the AL East.

The Orioles have a chance to make the East race much closer this weekend.

But much will depend on whether the Orioles’ rotation — the one that had struggled mightily before shutting down the Red Sox — can keep the recent roll going against the league’s most powerful lineup.

— Baltimore Sun