Kazmir, who has been on the disabled list with a left elbow strain since March, made his third and final rehabilitation start Monday night pitching for Triple-A Durham against the Richmond Braves.
"Felt great," Kazmir said. "Felt a little more stretched out from the very beginning. The fastball was there, changeup, slider, everything. I kind of just felt like I had a little bit more life on my fastball."
The Rays ace allowed one run on three hits -- one of which was a home run -- walking one batter and striking out three.
"He pitched well [Monday night]," Rays manager Joe Maddon said. "He felt good, got up to 94 mph, so what we're going to do is slot him in on Sunday."
Kazmir said he is 100 percent ready to go and fully recovered.
"I think it was a good decision just to be cautious like that because it is a long season," said Kazmir about the conservative approach the team took on his recovery. "You know you look at some guys, they try to come back early, they look good for a few starts. They might go back on the DL, or have some problems. I feel confident we got everything feeling good -- 100 percent, no symptoms, no nothing."
Kazmir looked happy to be back in the Rays' clubhouse and said he was very excited about the team's 14-11 start.
"We knew we were capable of doing this," Kazmir said. "So I don't really think this was much a surprise to us."
Kazmir was the first member of this year's team to talk about the Rays making the playoffs this season. Reporters teased him about making the bold statement and not backing it up because he missed the first month of the season.
"Hopefully, I can make up for it," Kazmir said. "I just want to contribute. I've watched them enough on TV. You just want to pull your hair out because you want to get out there and contribute and help the team. I'm just excited to be here now, ready to be back with the team."
Kazmir is 4-3 with a 2.73 ERA in nine starts against the Red Sox at Fenway Park, with 59 strikeouts in 52 2/3 innings. The left-hander is 6-5 with a 2.66 ERA in 17 career starts against the Red Sox, who are hitting just .218 against him. And now he'll be making his return in Boston.
"You've got to do it in style, right?" Kazmir said. "I'm not going to try to overthrow or do anything different. There's definitely going to be the adrenaline there."
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.