KANSAS CITY (AP) - The NFL is supposed to be a 16-game exercise in attrition.
Teams typically start off the opening week at full strength, and through the brutal grind of practice and games, guys pick up the inevitable bumps and bruises, and often injuries more serious than that. The teams that best cope with them are usually in the playoff hunt.
If the Kansas City Chiefs have any designs on returning to the postseason in fourth months' time, they'll have done so by taking a vastly different approach.
They'll have started off without Pro Bowl linebacker Tamba Hali, who was suspended for a 40-24 loss to the Falcons on Sunday. They'll have been without safety Kendrick Lewis, cornerback Brandon Flowers and defensive tackle Anthony Toribio, all due to injuries.
Hali will be back for Sunday's game at Buffalo.
The rest of them? Well, nobody seems to quite know for sure.
"Those guys will have to go out there and see what they can do," Chiefs coach Romeo Crennel said Monday, adding there were no new injuries coming out of the game.
An examination of the missing pieces takes a lot of the guesswork out of how Atlanta's Matt Ryan threw for nearly 300 yards and accounted for four touchdowns, and how wide receivers Julio Jones and Roddy White spent most of the afternoon at Arrowhead Stadium running in space.
While Toribio is a relative newcomer to the lineup, the other three each started 16 games last season, and combined for 184 tackles, a dozen sacks and seven interceptions. Hali went to the Pro Bowl for the first time, and Flowers was one of the biggest snubs.
"We knew we were limited a little bit, but we also felt like the guys we had behind them had to step and do the best they could do to help the team win," Crennel said. "That's what you do every week in the NFL, because you don't have all your players healthy for every game. You're going to miss guys sometimes, and then your backups need to step up."
Without them in the lineup, the high-powered Atlanta offense put together four scoring drives of at least 70 yards, piled up 376 yards of offense and punted just once. The Falcons converted only five third downs, but they faced just 10 of them.
"We couldn't stop anybody on defense, and that's a problem," Crennel said. "We have to build on the positives and eliminate the negative things, and we have a short period of time to do that."
Things weren't nearly as bad on the injury front as they could have been.
Derrick Johnson had been dealing with a sore ankle that limited him in practice, but the Pro Bowl linebacker managed to lead the Chiefs in tackles.
The trio of running back Jamaal Charles, tight end Tony Moeaki and safety Eric Berry all played after missing nearly all of last season with torn ACLs, which kept them out for most of the offseason and limited them early in training camp.
Still, a defense that was one of the league's best late last season looked like Swiss cheese against Atlanta. Backup safety Abe Elam and third-string cornerback Jacques Reeves were no match for the big, fast wide receivers that the Falcons were sending down the seams.
""We have to play better," cornerback Stanford Routt said simply.
While the Chiefs get missing pieces back for Week 2 at Buffalo, the Bills are taking the more typical path through a season: They lost a couple of key pieces in their opener.
Running back Fred Jackson and wide receiver David Nelson hurt their right knees in Sunday's 48-28 loss to the New York Jets. Both were due for MRI exams Monday.
C.J. Spiller ran for 169 yards and two touchdowns in place of Jackson, who appears likely to miss the game against the Chiefs. But the Bills may have a much harder time replacing Nelson, who emerged as a big-play threat for quarterback Ryan Fitzpatrick last season.