It wasn’t just a fluke.

Aaron Cook turned in a spectacular outing on Friday night in Seattle, blazing a complete-game shutout in just 81 pitches. He gave up just two hits (one of the infield variety, another a liner to the outfield), walked none, struck out two and threw 72 percent of his pitches (58 of 81) for strikes. It was an outing unlike any the Red Sox had seen in more than a decade. After all, the last time that the Sox received an outing of at least eight innings that required 81 or fewer pitches was in 1999, when Bret Saberhagen worked eight innings in 76 pitches.

But while the performance in the Red Sox’ 5-0 victory over the Mariners was unlike any other by a Boston pitcher in years, it was not unfamiliar territory for Cook. This was the sort of performance that, at his peak with the Rockies from 2007-09, defined him as one of the better pitchers in the National League. In 2007, he had a 74-pitch complete game; in 2009, he needed just 79 pitches for a complete-game shutout.

This is what a sinkerball can do when it is in peak form, eliciting feeble early-count contact that keeps a game moving at a blistering pace and, not only keeps a pitcher locked into his rhythm, but also denies an opposing pitcher the opportunity to catch his breath. Cook recorded 16 outs via grounder (with a pair of double play balls), facing just one batter over the minimum, as he claimed his second straight victory.

WHAT WENT RIGHT FOR THE RED SOX

– Will Middlebrooks snapped an 0-for-12 streak in a big way, breaking a scoreless tie with a solo homer to left field in the top of the fifth inning. He later added a single to finish with a 2-for-4 night. The contest was significant in underscoring that Middlebrooks is capable of pulling himself out of slumps, a trait that the Sox had seen once before in May and that ultimately helped convince the team that it was prepared to commit to the 23-year-old and trade Kevin Youkilis. On Friday, that faith was rewarded.

– Daniel Nava swung the bat well, blasting a colossal homer to right and later flying out to very deep left (a ball that might have been out or at least off the fence in other parks) while going 1-for-4 with his third homer of the year and a walk. He’s hitting .311 with a .917 OPS.

– Cody Ross continued to pound the baseball in his return from the DL, going 1-for-4 with a homer. He has four homers and five doubles in 11 games since coming off the DL, hitting .300/.333/.725/1.058 in that span.

WHAT WENT WRONG FOR THE RED SOX

– Truthfully, not much. Mike Aviles committed an error behind Cook, but the defense was otherwise spectacular. Every member of the lineup except Dustin Pedroia had at least one hit, though Pedroia had a terrific defensive game and hit a ball hard into the gap that Ichiro Suzuki tracked down; he also walked. So, the only thing that really went wrong for the Sox took place in Pawtucket, where Daniel Bard endured significant struggles.