Feldman threw his complete arsenal in his first start.
"That's how I pitched during the season, just trying to get a feel for everything as quickly as I can," Feldman said. "It usually doesn't come right away, but I've worked on everything and threw all my pitches today."
Brad Peacock followed Feldman with a quality third inning, but back-to-back singles from Miguel Cabrera and Victor Martinez and an Alex Avila walk put Peacock in a bases-loaded jam in the fourth.
Up came Jackson, who has been batting around the middle of the order so far this spring, rather than his usual leadoff spot. His soft line drive fell in front of a charging George Springer in short center field to plate Cabrera and open the scoring.
Peacock surprised Kelly with a first-pitch curveball, but followed with a fastball that Kelly drove into the gap in right-center. Jackson stopped at third, but Nick Castellanos and Hernan Perez emptied the bases with sacrifice flies.
"He threw a pretty good curveball on that first pitch," Kelly said. "I'd never faced him before, I think. He was throwing pretty firm. He seemed to cut [the ball] a little bit, too."
Brett Wallace provided Houston's lone run with an RBI groundout, scoring Carlos Correa in the sixth.
Kyle Lobstein, filling the rotation spot that awaits Justin Verlander's return to game action, became the first Tiger this spring to pitch three innings. He held the Astros hitless, allowing only a walk while striking out four of the first seven batters he faced, with a good change of speeds.
The win drew the Tigers (3-2) back to their winning ways after Detroit lost both ends of a split-squad day Friday. Houston fell to 1-1.
Up next: The Astros play their Grapefruit League home opener on Sunday when they face the split-squad Braves at 12:05 p.m. CT at Osceola County Stadium in Kissimmee, Fla. Right-hander Jarred Cosart, who went 1-1 with a 1.95 ERA in 10 starts in his Major League debut last year, will throw for the first time this spring. He is scheduled to pitch two innings.