KANSAS CITY, Mo. (AP) - Alex Smith threw three touchdown passes, Dexter McCluster returned a punt 89 yards for another score and the unbeaten Kansas City Chiefs plunged the New York Giants to 0-4 with a 31-7 victory on Sunday.

Smith hit touchdown passes of 4, 2 and 35 yards for the Chiefs, who under Andy Reid have already doubled their victory total of 2012. They are the second team to go from a two-win season to 4-0 the next year.

The Giants, who trailed only 17-7 after three quarters, are 0-4 for the first time since 1987.

Eli Manning connected with Victor Cruz on a 69-yard scoring play for New York's only score. The Kansas City defense sacked Manning three times. Smith was intercepted twice, the first giveaways by the Chiefs, who also lost a fumble.