A.J. Burnett isn’t the only one to blame. Some of it falls on the Yankees’ absent offense and defense, and some of it’s about giving credit to Josh Beckett and the Boston Red Sox.

But Tuesday night’s loss at Fenway was mostly about Burnett’s haplessness on the mound. He couldn’t throw a fastball for strikes, and he couldn’t throw a curveball for strikes, and since those are his two primary pitches, it follows that he couldn’t throw much of anything for strikes. Less than three innings and eighty-four pitches after taking the mound, Burnett had surrendered five runs, two of which came on a loud David Ortiz homer to deep center. Loud when it happened, loud when it drew a curtain call from the Fenway crowd.

It was only his third home run of the season. Nobody has to be told it wasn’t the Big Papi Yankees fans have come to fear standing there at the plate. This was an Ortiz who hasn’t been Big Papi all season. An Ortiz who’s been getting far more catcalls than curtain calls at his home ballpark. An Ortiz whose batting average has barely scratched .200, who’s hitting .188 against righties, who was dropped from third to sixth in the batting order,  who’s been benched in several series, and who Peter Gammons and others have reported has come close getting acquainted with the bench for a lot longer.

But there he went and did it, hitting one out against the Yankees for old times’ sake, laying into a four-seam fastball Burnett served right over the middle of the plate at 95 mph, right over, which only means that ball wanted to introduce itself to the sweet spot of his bat in a hurry.

Burnett wouldn’t be helped that inning by a fielding error committed by Alex Rodriguez, his fourth of the season. With one out, and outfielder Mark Kotsay having strolled to first after taking four consecutive fastballs that never came close hitting the plate, Red Sox shortstop Nick Green hit a hard grounder to third, and A-Rod seemed caught between going the easy out at first or a double play he wouldn’t have gotten anyway, and held onto the ball too long in his indecision. And then neither Green nor Kotsay were out, and couple of batters later both of them scored on a double.

Four-zip Sox. Second inning. You get them going at Fenway Park, you stake Beckett to that kind of early lead, and you are in serious trouble.

Again, the Yankees defense was complicit in the loss. There was Jorge Posada’s passed ball, and Robinson Cano missing a groundball to second that was ruled a hit but was a play he should have made.

The Yankees play eighteen errorless games, set a Major League record, and now all of a sudden they can’t go a single game without making one. Go figure. At Fenway, you can’t afford that. It helps lose games. Far less importantly, it forces out-of-market fans watching those games on NESN, the television home of the Red Sox, to hear their fill-in color commentator, resident baseball whiz and king of objectivity Dennis Eckersley, try to sell the argument that a record-breaking errorless streaks doesn’t mean a team’s played good defense during that streak.

Again, go figure.

But the big thing is the loss. This one, most of it, the sixth Yankees loss to their archrivals in as many games this season, falls on Burnett.  He began poorly and never got himself straightened out, which is a mystery. This is not some inexperienced rookie pitcher we’re talking about. This is a 10-year veteran. Somebody who never used to lose against the Red Sox and killed the Yankees on his way to winning 18 games with Toronto last season. This is someone the Yankees signed for five years at $82 million to be their No. 2 starting pitcher. And he couldn’t adjust.

Can we throw in one last “go figure?”

In his postgame comments, manager Joe Girardi attributed Burnett’s wildness to too much rest. He hadn’t pitched in seven days as a result of Girardi’s decision to reinsert Chien-Ming Wang into the Yankees’ rotation, and then a rainout last Friday.

“It was control, and I’ll take the blame for that. I mean, it’s hard to pitch on seven days,” Girardi said. “A guy’s used to a routine, and we tried to change our rotation a little bit to separate some people, and insert Chien-Ming Wang, and you can’t have too many expectations of a guy’s command.”

But Girardi was skirting around the widespread perception that he’d largely changed the rotation to avoid leading off the series with Wang, who’s still working back into form, on the mound. Putting it another way, he thought Burnett had a better chance of getting things off to a solid start for the Yanks.

His explanation for Burnett’s lack of command is also based on suspect logic. Monday night at Yankee Stadium, Phil Hughes had no trouble throwing quality strikes for a scoreless seventh-inning after cooling his heels in the bullpen for well over a week. Last Thursday, Wang managed to throw a decent ratio of strikes-to-balls in his first start since returning from rehab. If they weren’t too strong, why was Burnett?

After the game, YES studio analyst David Cone commented that the good pitchers, the really good ones, are supposed to be able to make the adjustments. He ought to know. He once ranked among the best.

And let’s add Beckett to the list. As Johnny Damon would point out, he’d also labored through the early innings, struggling with an inability to locate his off-speed pitches. But, said Damon, Red Sox catcher Jason Varitek noticed that Beckett’s four-seamer was working best for him and repeatedly called for it until he could spot it over the plate — and then build off it until he got a feel his curveball.

The Burnett-Posada tandem could accomplish no such thing. And when interviewed in the visiting clubhouse, even Burnett wouldn’t let Girardi’s too-much-rest, too-strong, explanation take him off hook.

“There’s no excuses,” he said. “I mean, I was out of whack, and I don’t think I repeated a delivery the whole two innings I was out there. So that’s just, you know, Skip being Skip.”

Translated: That’s just the manager expressing confidence in his player and casting his poor performance in the best possible light.

Girardi trying to take some of the heat off him is commendable — but it won’t erase Burnett’s ineffectiveness, or change the fact that he’s only won four out of his 11 starts for the Yankees and is carrying a 4.89 ERA into June.

Whatever the reason, Burnett has underperformed to this point. At Fenway Tuesday night, he appeared to be pitching not to lose rather than pitching to win — and to a point that’s how his team appeared to be playing behind him

Six games against the Red Sox, six losses.

If the Yankees are going to win the AL East in 2009, that will have to change.

Tonight would be good time to start.