FORT MYERS, Fla. (AP) — Boston Red Sox right-hander John Lackey passed another test Tuesday in his comeback from elbow surgery, pitching into the sixth inning against Tampa Bay minor leaguers.

Lackey, who missed last season following Tommy John surgery, gave up three runs and six hits in 5.1 innings against players from Triple-A Durham. He walked four and struck out seven.

While the Red Sox enjoyed their final scheduled off day in spring training, Lackey faced 26 batters and threw 101 pitches, 54 for strikes.

“Felt good,” he said. “Got to the number of pitches I wanted to get up to. Got up six times. Got what I needed accomplished and keep moving forward.”

When the Red Sox break camp this weekend to head to New York for Monday’s season opener against the Yankees, Lackey will stay behind and have one more outing Sunday in an intrasquad game before rejoining the team. He is expected to go four innings and throw about 60 pitches.

It has been a confidencebuilder for Lackey to pitch with no restrictions this spring — and without concerns about his surgically repaired right elbow.

“It’s not a situation of thinking about the elbow,” he said. “Just trying to get my pitches in and improve on things I need to do to get ready for the season.

“Everybody who has surgery has doubt, for sure, when you first start throwing. Got a big zipper in my arm for a reason. At the end of last season when I came down here and threw two innings, I felt pretty good about that. Things went well and I had a normal offseason and that was nice in terms of confidence coming into this season.”

Lackey’s spring training and rehab process has gone about as well as the Red Sox could have hoped.

“It’s been a very smooth ride, even after the stress of throwing three innings, four innings, five innings twice,” pitching coach Juan Nieves said.

“His bullpens have been full, 44, 45 pitches. There was one bullpen he threw 52 pitches and he felt great even after a long start. So that shows me health. If he was dragging after (an outing), first of all, starting a bullpen, the ball not coming out, second of all, if I see arm-angle changes when they’re looking for the spot that they feel it doesn’t hurt. But I haven’t seen that. So it’s been a very pleasant spring training for him. And I know it’s been a little longer for him because he’s had that extra start. And he’s going to have a start here the day after we leave. But I’d rather have him throw here under game speed and warm weather than the weather in New York.”

Lackey has made seven starts this spring, including two in minor league games and one in an exhibition against Puerto Rico’s World Baseball Classic team.

The 34-year-old Lackey is in the fourth season of an $82.5 million, five-year contract.