Kellen Clemens, in the Redskins’ final preseason game Sept. 1. (Toni L. Sandys / Washington Post)

The Houston Texans placed Schaub, who is expected to undergo surgery, on the season-ending injured-reserve list and signed Kellen Clemens, who was with the Washington Redskins in training camp and preseason. He was released in September.

Clemens will be the No. 3 quarterback, after Matt Leinart and rookie T.J. Yates. The Texans play Jacksonville on Sunday.

The Texans had also looked at Jeff Garcia, Trent Edwards and Brodie Croyle, but went with Clemens in part because of his experience in Mike and Kyle Shanahan’s system in Washington. The Texans run the same system.