The Indianapolis Colts, meanwhile, are still looking for an answer behind Andrew Luck.
Rudock took advantage of the injury-depleted Colts by throwing two touchdown passes to Kenny Golladay, driving the Lions to a short field goal and leading them to a 24-10 victory in the preseason opener on Sunday.
"You can see the difference between last year and this year at this time," Lions coach Jim Caldwell said. "He has a better grasp of things around him. He's in command."
The second-year quarterback played most of the first 2½ quarters and wound up 13 of 21 for 142 yards. Stafford played one series, going 2 of 3 for 36 yards and left after throwing an interception.
All the Lions needed against the injury-depleted Colts was Rudock's 23-yard TD strike to Golladay in the first quarter.
But Rudock also threw a 15-yarder to Golladay in the second and set up Matt Prater for a 28-yard field goal to make it 17-3 at the half. Detroit closed out its scoring with a 15-yard TD pass from Brad Kaaya to Dontez Ford.
With Luck still on the physically unable to perform list following offseason surgery on a partially torn labrum in his throwing shoulder, the Colts sputtered.
Indy finished with 230 total yards — 90 on its final drive — and 14 first downs. Their only points came from Adam Vinatieri's 42-yard field goal in the first half and a 1-yard TD plunge from Troymaine Pope as time ran out.
For the second consecutive year, the Colts arrived for their preseason opener with a stadium in need of a little touch-up paint. But instead of having to cancel the game, like last year's Hall of Fame game, the field crew cordoned off two areas with the words "NFL Play Football" and fixed them. Team officials said the paint was too thick. A little less than two hours later, the kickoff was right on time.
In addition to Luck missing the game, Indy also played without center Ryan Kelly (foot), left guard Joe Haeg and running back Frank Gore. Among the Lions sitting out were left tackle Taylor Decker and defensive end Ezekiel Ansah, who are on PUP, and right guard T.J. Lang.
Lions: Golladay, a third-round draft pick, made a good first impression with three catches for 53 yards, including two nifty scores. Teez Tabor wasn't bad, finishing with three tackles.
Colts: The knock on first-round draft pick Malik Hooker was that he missed too many tackles in college. Not Sunday. Hooker finished with four tackles in limited work and made a touchdown-saving shoestring tackle in the second quarter.
Lions: Stafford was solid in his brief appearance, and Rudock impressed. Kaaya played well, too, going 8 of 11 with 71 yards with the TD.
Colts: Scott Tolzien was 2 of 5 for 24 yards and picked up only one first down in three series. Walker, an undrafted rookie from Temple, showed flashes while finishing 9 of 20 for 86 yards. Stephen Morris, who spent most of the past two years on Indy's practice squad, didn't enter until the fourth quarter and was 13 of 20 with 94 yards.
Lions: Defensive end Kerry Hyder Jr. did not return after being carted off the field with a lower left leg injury in the first quarter. Afterward, Caldwell said it looked like a "significant" Achilles tendon injury. The Lions also lost defensive end Brandon Copeland (shoulder) in the second half.
Colts: Linebackers Sean Spence and Deiontrez Mount both left with injured hamstrings and did not return.
Lions: "It makes you sick to your stomach when you see a guy like that go down," Golladay said when asked about Hyder. "I hope the kid's all right."
Colts: "There are a lot of things to clean up," Colts coach Chuck Pagano said. "We're going to grind it. We've got to make corrections."
Lions: Host New York Jets on Saturday.
Colts: Visit Dallas on Saturday.