They've won at least 10 games and made the playoffs three of the last four years
They also have Tony Gonzalez, a Chief from 1997 to 2008.
In the first quarter, Falcons' Matt Ryan to Julio Jones, makes it 7-0, Atlanta
Second quarter, it's 10-3, Atlanta when Matt Cassel finds Kevin Boss - makes it 10-10
Also in the second, the Falcons come roaring back - Ryan to Jones again, makes it 17-10. Ryan moves the ball 299 yards, and three scores. Chiefs down 20-to-17 at the half
In the third quarter, Chiefs down 27-17 when Ryan hit Gonzalez.
Chiefs lose 40-24. They go to Buffalo next Sunday.
Official game recap from the Kansas City Chiefs:
The Kansas City Chiefs started opening day without four defensive starters against a high-flying offensive attack from the Atlanta Falcons. The Chiefs fell to the Falcons 40-24.
The Falcons got into the end zone first when WR Julio Jones caught a short pass from QB Matt Ryan with 8:56 left in the first quarter. K Matt Bryant's extra point was good putting Atlanta on the board first 7-0.