Left tackle Eric Fisher didn't suit up for Kansas City in their season-opener.

Shaun Smith, a defensive lineman for the Chiefs from 2010-12, thinks he knows why -- and it has nothing to do with Fisher's sprained ankle.

Smith never played with Fisher on the Chiefs, so he'd have no idea about Fisher's mental make-up. It seems unlikely he'd bow out of the first game just to avoid a superstar player, though.

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Yet Smith's comments underscore a growing sense of concern with the player picked first in the 2013 NFL Draft.

Fisher simply hasn't developed the way the team has expected. He lost the starting left tackle job this preseason to Donald Stephenson. And he couldn't gear up for Sunday's game against the Texans, leaving newly-signed Jah Reid to contend with Watt, Jadeveon Clowney, and Co.

Smith isn't the only one frustrated with Fisher. The Chiefs probably want more return on their investment, too.