The loudspeakers at Citizens Bank Park blast Philly soul as the Indians’ Scott Kazmir, the erstwhile Met prodigy who blossomed elsewhere, slowly walks off the mound in the sixth inning of his start last Tuesday. “When Will I See You Again,” a 1974 hit by The Three Degrees escorts Kazmir to the dugout, part cheeky sendoff to an opposing pitcher and, in a way, part career comment.

That’s the kind of question the baseball world was asking about Kazmir for two lost years. The lefty once was a fireballing phenom, an All-Star twice by age 24 and a centerpiece of an emerging Rays contender. But he had the career trajectory of a firework, streaking skyward and burning brightly awhile, then fizzling into nothingness.

He made one April start for the Angels in 2011 and was later released at age 27, his fastball sputtering, his mind spinning. He spent last year trying to recapture his 96 miles-per-hour heat and his sharp slider in an independent league, a sick feeling blooming in his stomach every time he saw a Major League Baseball game on television.

When it all went away, where did it go? Kazmir thinks injuries started a chain reaction that fouled up his pitching mechanics when he tried to play through them. The mound was always a home of sorts for Kazmir, but he was lost, “trying to get hitters out with no clue where the ball is going, throwing 84,” he says. “How did this come so far?”

Still, he insists, he was certain he could get it all back if he worked hard enough. Kazmir is only 29, after all. So he endured dawn bullpen sessions at home near Houston. He pitched for the nearby Sugar Land Skeeters in the independent Atlantic League, marveling when then-teammate Roger Clemens brought in celebrities like country star Toby Keith, who once stood in the batter’s box while Clemens threw, using his cellphone to take video of The Rocket’s motion. He went to winter ball in Puerto Rico. His fishing boat — he’d go for bass in Houston-area lakes or for redfish in Galveston Bay — offered sanctuary.

Most of all, a pitcher who once “didn’t know how I did it, I just did it,” learned his motion. He deconstructed the pistons and cogs of his windup, how to repeat his mechanics and repair them. It’s left him with another kind of feeling, deep down.

“I feel like I’m going to be way better than I was,” Kazmir says. “Definitely.

“I had all my good years early in my career and I always felt like that was just the tip of the iceberg, that was just the beginning. To have it slip away — I’m not going out like that.

“I have so much more to offer.”

It’s hard to call what Kazmir is doing now a full-blown comeback, just because the sample size is just too small. Monday will be just his sixth start for Cleveland since signing a minor-league contract and winning a rotation spot in spring camp. His ERA is 5.33. He is 2-2 and has allowed 29 hits — seven of them home runs — in 25.1 innings.