Moore found time in the pocket to hit Fuller on a perfectly placed 25-yard touchdown pass over the middle with 9 seconds left in the second quarter to put the Lions ahead 17-0.
"It was a great ball, just needled it right through and I just had to run underneath it," said Fuller of his second touchdown this preseason. "It was just another chance to be in the end zone to show the team here and to show other teams what I can do."
Fuller, part of a multi-receiver competition for one of the team's final spots, finished with a team-best 43 yards receiving in helping the Lions finish the preseason at 3-1.
Moore finished 17 of 28 for 172 yards and two touchdowns and is attempting to hang behind backup Dan Orlovsky.
There are deeper concerns in Buffalo (1-4).
The Bills produced another dud on offense during a three-drive cameo appearance. They also watched Watkins, their most dynamic threat, leave a game with bruised ribs for the second time in three weeks.
Marrone declined to provide an update on the severity of the injury. And he defended his decision to play Watkins, who sat out a 27-14 loss to Tampa Bay on Saturday after he hurt his ribs a week earlier at Pittsburgh.
"One of the big questions was the quarterback and Sammy. They haven't played a lot of games," Marrone said. "I always get concerned when people come out, especially when you're a rookie. You've got to play."
Watkins, however, isn't just a normal rookie after the Bills invested heavily to land him in the draft. Buffalo traded its 2015 first-round pick to Cleveland to move up five spots and select the Clemson product with the fourth pick.
"It was a tight throw, and he probably just got a little banged up," Manuel said. "He'll be fine."
Manuel went 3 of 7 for 56 yards and was sacked twice.
Jordan Palmer unraveled in his debut for Buffalo. He went 9 of 22 for 73 yards passing and three interceptions two days after being signed to compete for a backup spot.
The Lions' defense continued its postseason string of first-half domination. Detroit gave up 97 yards net offense, had four sacks and safety Isa Abdul-Quddus' interception of Palmer's pass set up the first touchdown in the opening 30 minutes. The Lions finished the postseason allowing just six points in the first quarter and 22 in the first half.
"Any time you can keep a team in the National Football League off the scoreboard, it's a pretty good night for your defense," Caldwell said. "We still have some work to do, but overall, I thought it was a decent performance."
Copyright 2014 by The Associated Press