It can’t get much uglier for Clay Buchholz.

He’s the first pitcher in major league history to allow five or more runs in each of his first six appearances in a season.

If he does it again on Friday, he’d be just the fifth pitcher in MLB history to allow five or more in seven straight starts (regardless of when they occurred in the season).

It’s a remarkable downturn for a pitcher who just two years ago finished second in the American League with a 2.33 ERA. Thanks to his current 9.37 ERA, Buchholz would need to throw 95 consecutive scoreless innings to get his ERA down to that level.

Over the past 100 years, no Boston Red Sox pitcher has allowed more earned runs in his first six starts than the 33 given up by Buchholz. In fact, the only other pitcher to give up 30 runs was Howard Ehmke in 1926. He only lasted another eight games with the Red Sox before getting shipped away in a trade.

As ugly as 2012 has been for Buchholz, he’s still managed a team-leading three wins. Of course, all of those came when allowing five or more runs. The last Red Sox pitcher with more such wins in a season was Gene Conley with five in 1962.

Indeed, Buchholz has been the beneficiary of the best run support in the majors (7.4 runs per start). To put it another way, Buchholz still has a 7.58 ERA in his three wins. His two no-decisions? A 14.09 ERA.

Buchholz recognizes how fortunate he’s been.

"The way I've been pitching I deserve to be 0-6 right now,'' Buchholz said following his last outing. "I'm lucky not to be that in wins and losses. I've got to do my business. They score runs for me every time, and I keep taxing the bullpen. I gotta figure something out.''

Red Sox starters now have a 7.24 ERA at Fenway Park, and Buchholz’s 8.10 ERA in four home starts in a big reason why. For Buchholz, the long ball has been devastating at Fenway.

All 10 of the home runs he’s allowed have come at home. That puts him easily on pace to break Tim Wakefield’s record of 25 allowed at Fenway in 1996.

It’s a stark contrast to the previous two seasons, in which Buchholz allowed a combined two home runs at home.

Ironically, Buchholz is allowing a lower percentage of fly balls in 2012 than he did in 2010.

Only about nine percent of fly balls are hit for home runs. Right now, 29 percent of fly balls allowed by Buchholz have gone out of the park. That’s easily the highest in the majors. In 2010, it was fewer than six percent.

A closer look at the 10 home runs he’s allowed shows just how far Buchholz has fallen.

Opposing eight and nine hitters are batting .500 with four home runs. Six of the home runs have come with two strikes. Opposing hitters are batting .333 with a 1.091 OPS with two strikes against Buchholz.

As if all these numbers didn’t already make it obvious: Buchholz has been the least productive player in the majors this season. His -1.3 WAR (wins above replacement) ranks last in the majors.

So what’s the cause of this mound mayhem?

As Gordon Edes recently wrote, even Buchholz doesn’t have the answer.

"Obviously, something is going on -- tipping my pitches, or maybe not throwing the right pitches at the right time,” Buchholz said. “I've sort of prided myself on knowing how to pitch the last couple of years and being able to throw pitches in different counts and sometimes fool hitters, but it's not working right now.”

With numbers this bad, you can find fault everywhere. Pick a pitch and the numbers will back it up.

Fastball: Buchholz has lost two miles-per-hour on his fastball since 2010. But a bigger issue than velocity has been location. In each of the previous two seasons, 33 percent of Buchholz’s fastballs were thrown down in the zone. This year, it’s just 26 percent. All those high fastballs have come at a cost: seven of the 10 home runs allowed by Buchholz.

Changeup: Two years ago, the changeup was Buchholz’s best pitch. He threw it 17 percent of the time and opponents would miss with almost half of their swings (47 percent). This year, it accounts for just 12 percent of his pitches and opponents swing and miss just 28 percent of the time. He’s also not locating the changeup, throwing it for 55 percent strikes, down from 62 percent in 2010. Opponents are hitting .471 with a 1.324 OPS on plate appearances ending in his changeup.

Cutter: Buchholz is throwing more cutters than ever, possibly leaning too heavily on the pitch. It’s accounted for a career-high 20 percent of his pitches this season, but he’s not getting anyone to swing and miss. Opponents are hitting .360 on his cutter in 2012.

Curveball: Opponents are hitting .333 with two strikes. League average is .181. Buchholz simply isn’t putting hitters away, and part of the reason is his curve. He’s throwing 27 percent curves with two strikes, up from 16 percent a year ago.

No matter whether the cause of Buchholz’s struggles or merely symptoms, the numbers tell a frightening tale.

“It's got to change, though,” Buchholz said. “I don't think there's anyone in the history of baseball who's gone through a whole season giving up five runs every start.”