BOSTON — There’s a fine line between being a great pitcher and one that’s … not so great.

Gerrit Cole is finding that out in his comeback from Tommy John surgery and Saturday, he showed a little bit of both.

Unfortunately for the Yankees, by the time the former Cy Young winner got back to his old self, he’d put the team in too big a hole to overcome.

But despite a second straight shaky outing in a 4-1 loss to the Red Sox, Cole said he was encouraged by how he felt over his final three innings compared to his rough first 2 ¹/₃ innings.

“I got more aggressive as the game went on,’’ Cole said.

The difference, according to Cole and Aaron Boone, was that after trying to be too careful in the early going and seeing his command suffer, Cole went on the attack more in the latter part of his outing.

The results backed that up.

He gave up solo homers to Masataka Yoshida and Anthony Seigler, both from the left side, in the first two innings.

And after giving up singles to Yoshida and Ceddanne Rafaela to open the third, Cole then allowed a booming two-run double to Willson Contreras.

Cole righted himself after that, retiring nine of the next 11 batters.

The turnaround didn’t help the Yankees avoid a third straight loss, but as Austin Wells said, it may have given Cole some momentum heading into his next outing.

“I tried to free myself up,’’ Cole said. “The command sometimes isn’t there. You have to go after it then and not care as much about where the pitch is going.”

Not every pitcher can do that without disastrous results.

As much as the Yankees and their slumping offense can ill afford shaky starts from their ace, the team is looking for Cole to round into peak form as the season moves along and not necessarily in June, seven starts post-elbow surgery.

Cole allowed four runs in 5 ¹/₃ innings to the Red Sox and has given up nine runs in 9 ²/₃ innings in his last two outings.

---

• CHECK OUT THE LATEST MLB STANDINGS AND YANKEES STATS

---

Perhaps Boston wasn’t the place to call on Cole for dominance, since Fenway has been his Kryptonite for much of his career.

Of any ballpark in which he’s made more than three starts, Cole has the worst ERA (5.52), WHIP (1.409) and opposing OPS (.864) with the Green Monster behind him.

Saturday was more of the same.

The homer to Yoshida to lead off the bottom of the first, the home run to Seigler and the double to Contreras were all on four-seam fastballs, which Cole threw less than usual Saturday.

He responded after the Contreras double by whiffing the next two batters and gave up just a pair of singles the rest of the way.

“Coming off surgery, he’s slowly starting to unlock and feel like himself again,’’ Wells said. “He started to free himself up again after trying to be too perfect. He’s been carrying that a little bit. He was able to break free the last couple of innings, just go out and pitch and not worry too much about results. That freed him up and gave him some good momentum going forward.”