Clay Buchholz shows excellent stuff and has command of his off-speed pitches in his six-inning performance for Double-A Portland.

AP / Joel Page

PORTLAND, Maine — The resurrection of Clay Buchholz began in earnest last night, in a spot no one ever expected to see him in again.

So confident were the Portland Sea Dogs of that fact that long before the season began, they had planned this as “Clay Buchholz Bobblehead Night.”

Little did they know that the real Clay Buchholz would show up and bring the old Clay Buchholz with him.

Sent down last week to Double-A Portland, where he sizzled for half of last season, to repair his shattered confidence and his mastery of the strike zone, Buchholz showed that he has the stuff.

Even if it’s two levels below and miles away from Fenway Park.

More importantly, he proved that to himself.

“I felt really good,” Buchholz said. “There were a lot of mechanical things that I’ve been thinking about, that I didn’t try to think about [tonight]. I went back to what I did last year when I was here. They seemed to work real well for me. So I tried to revert back to that a little bit.”

Buchholz allowed five hits, fanned eight (seven swinging) and didn’t walk anyone over six innings.

And as often as not, he showed command of his repertoire, especially his selection of curveballs and changeups.

Although he left with a 5-4 lead, he did not factor in the decision.

Buchholz struggled in only one inning, the third, when New Britain scored three runs on as many hits.

The velocity was there — he clocked 95 mph on the radar gun four times — and he appeared to be more comfortable with his breaking ball.

“It’s a good pitch,” said Buchholz, “when I have the confidence enough to throw it. That’s what I’ve been lacking a little bit.”

Buchholz breezed through the first two innings, allowing only a single up the middle to Daniel Berg.

But in the third, the Rock Cats connected on his fastballs, with Radolfo Palacios and Brandon Roberts both singling before Matt Tolbert — who is down from Minnesota to rehab his injured thumb — laced an RBI double.

“He threw great,” said Tolbert. “He’s got tremendous stuff. We just battled against him. But a pitcher like that, anytime you can get a few runs off him, that’s really good.”

Before the inning was over, New Britain had scored two more runs on infield groundouts.

Buchholz settled down after that, retiring nine Rock Cats in order, fanning four of them.

He gave up another run, unearned, in the sixth, then called it a night. “It felt like when I committed to a pitch,” he said, “they either hit it weakly or didn’t hit it at all. It’s coming along.”

Buchholz said that although he wants to get back to Boston as soon as possible, he’s prepared to spend the rest of the season in Portland if he has to.

“If I get a chance to go back up there in September,” he said, “I’ll go back up there with more confidence. If not, I’ll go home and have some building to do. Either way, it’s going to turn out good.”

In the New Britain pitching rotation is Pawtucket native Jay Rainville, who, in his first year at Double A, is 9-9 with a 5.98 ERA.