Third Down Lost Seattle. It's the Whole Story for Denver.

Chiefs Kingdom, the perfect start is gone, and the reason is simple enough to fit on one line: third down.

Our Take: Forget the kicker debate for a minute. Kansas City lost Sunday night because it couldn't stay on the field on offense or get off it on defense. Fix that and Denver is winnable.

The Chiefs went 3-of-11 on third down in the 20-3 loss, per NFL.com and KSHB. Seattle went 11-of-16, per KSHB and the Chiefs' official site.

Andy Reid put it plainly: "Third downs on both sides of the ball, we can do a better job on those," per KSHB. "All three phases, we struggled," he said, per the Chiefs' official site and KMBC.

The offense never found the end zone, per NFL.com and AP.

What to watch: Sunday's division game in Denver, a matchup with real AFC West stakes, per KSHB and Yahoo Sports. Win the money down and the Chiefs are right back on top.

Sources: NFL.com, KSHB, Kansas City Chiefs, KMBC, AP News, Yahoo Sports