PORTLAND, Maine -- Chris Sale was right where he wanted to be on Thursday.

"I miss this. I've had a lot of time away from this," Sale said. "The feeling that I get out there, I can't replicate it. I enjoyed how I felt out there. It's so much a part of who I am. It's what I'm supposed to be doing. I genuinely love playing baseball."

Making his first rehab start above the complex level as he makes his way back from a rib-cage stress fracture, the 6-foot-6 left-hander struck out seven while throwing 36 of 52 pitches for strikes in the Double-A Portland Sea Dogs' 15-4 win over the New Hampshire Fisher Cats. He allowed one run on four hits and did not issue a walk.

"Today went well. Honestly, I was expecting to go back out [for the fifth]," he said. "If they told me I was starting [for the Red Sox] five days from now, I would be excited for that. If I can get through five, six innings and be like I was today, I think I'd be ready to go. But my hands are off the wheel."

The seven-time MLB All-Star touched 96 mph and threw several pitches at 95 while getting swings and misses on his slider, but he was especially pleased with his feel for his changeup -- one of his main points of focus for his offseason work.

"The two things I needed to work on coming into this year were arm strength and that third pitch. I need that," he said.

"Velo comes and goes. ... For me, I worry about, 'What are the reactions of the hitters? How are they responding?'" he said. "Velo's good. And it's fun, but where I'm at, what I'm trying to achieve, it's not the end-all, be-all. It's nice that it's there, but 96 to me today is as important as the socks I'm wearing."

Sale made two rehab appearances with Portland as he made his way back from Tommy John surgery last summer. Those outings went well -- he was unhittable in the first and fanned nine in the second -- but he was happier with the way everything felt this time around.

"I feel like last year when I was here, I was searching for some stuff," he said. "I was still working on some things. Now, I feel like I'm just starting to sharpen things, just starting to build."

The damage the Fisher Cats did against him was not particularly jarring. Blue Jays prospect Cam Eden started the New Hampshire third with an infield single. Chris Bec followed with a double off Hadlock Field's Maine Monster, which was inexpertly played by Sea Dogs left fielder Tyreque Reed to allow Eden to score from first. Orelvis Martinez, MLB's No. 29 prospect, singled off Sale in the fourth after striking out in the second.

"They hit bad ones today. I threw a changeup that was up, I hung a breaking ball, and they made me pay," Sale admitted. "But the good ones were good."

Asked if recent conversations surrounding the vaccination status of Red Sox players would mean a change for Sale, the lefty was reticent.

"No. I just had a lot of fun. Let's not ruin that. I'm enjoying this process," he said. "I appreciate being where I'm at and what I'm doing. Today's today and tomorrow's going to come. We'll figure that [stuff] out in a month."

But, he reiterated, it's back with the Red Sox he's itching to be.

"That's what this whole process is for," he said. "I love being [in Maine]. I love the guys in Worcester. My boys down in Florida -- they know I love them. But this whole process is getting back to Boston and do what I need to do ... and help that team win."