The Kansas City Chiefs can thank their opportunistic defense for keeping their perfect start intact. Sean Smith returned an interception 100 yards for a touchdown and Tamba Hali scored on an 11-yard fumble return in a 23-13 win over the Buffalo Bills on Sunday. The Chiefs gave up a season-worst 470 yards to a Bills offense that was led by undrafted rookie Jeff Tuel, making his first career start. Kansas City (9-0) remained the NFL's only undefeated team and matched the best start in franchise history set in 2003. More...