PONTIAC, MICH., SEPT. 16 -- The Atlanta Falcons continued to play the heavy today, and this time it worked against them.

The Falcons' aggressive defense held Detroit to 51 second-half yards, but key penalties hurt and the Lions hung on to win, 21-14.

"It's our style of play," said Falcons Coach Jerry Glanville, who brought his smash-mouth brand of football to Atlanta this season. "That's the way we play. We're an aggressive team and we play hard."

Detroit quarterback Rodney Peete completed 13 of 26 passes for 167 yards and two touchdowns, all in the first half. After an ineffective third quarter during which he threw his second interception, Peete was replaced with 9:38 left in the game by Bob Gagliano.

"That's not the thing that usually happens to me, coming out slow in the second half," Peete said. "I need to concentrate on coming out better in the second half."

The Falcons (1-1), who overwhelmed Houston, 47-27, with their intimidating defense a week ago, were penalized six times for 79 yards, including three personal fouls, against the Lions (1-1).

"Atlanta is a team that tries to intimidate you," said Detroit linebacker Chris Spielman, who led all defenders with 10 tackles. "But you're not going to come into the Silverdome and intimidate us. If you're a professional football player and you get intimidated, you should look for another line of work."

The Falcons paid dearly for the rough stuff.

Atlanta had the Lions struggling and in a third-and-10 situation at the Detroit 14 with just over three minutes remaining when Aundray Bruce was flagged for roughing Gagliano after an incompletion.

Given new life, the Lions were able to pick up two more first downs and run out the clock.

"I didn't see {the Bruce hit}," Glanville said. "I never saw it. It was unfortunate because we gave such a good effort and Bruce was trying to help get us out of a hole.

"I'm proud that we totally shut them down offensively in the second half. We had the opportunity to win the ball game, but we didn't do it. . . .

"I take full credit for the loss. I see a lot of things that can be fixed, but I can fix them."