Watch to watch for: 49ers at Chiefs

Three things to watch for as the Kansas City Chiefs whost the San Francisco 49ers on Friday. Kickoff at 8 pm. ET:

Smith sees his former teammates: New Kansas City starter Alex Smith faces his former team. The No. 1 overall draft pick by the 49ers in 2005, Smith slowly became a steady player for the 49ers. Young star Colin Kaepernick replaced Smith at beginning of last season. It’s the preseason, but I’d expect to see a fired-up Smith.

More return explosion? Dexter McCluster, Knile Davis and Devon Wylie all had long returns last week. Nothing can spark an offense like a great return. Let’s see if the Chiefs can make a habit of it.

First-team defense: The Chiefs’ first-team defense was outstanding at New Orleans. This group is working well under new coordinator Bob Sutton. Let see what this unit can do against another strong offense.