Dobbins downplayed the pressure of replacing Cushing, Houston's leading tackler in 2009 (133) and 2011 (114).
"I'm not him, of course," he said, "but I will try to do my best to fill in his shoes."
Ruud started 68 games for Tampa Bay between 2005-10. He started nine games for Tennessee last season, making 57 tackles and deflecting three passes. He played in three games for the Saints before he was released on Monday. Next stop, Houston.
"They just kind of said, 'Hey, learn as much as you can, as fast as you can,'" Ruud said. "That's kind of my goal right now."
Kubiak said fourth-round draft pick Keshawn Martin will take over punt and kickoff return duties, an area where he excelled at Michigan State. The 5-11, 190-pound Martin ranks second in school history in punt return yards (659), eighth in kickoff return yards (1,100) and 10th in all-purpose yards (4,013).
"You've got to hit it and get it on those things," Martin said. "I've got my opportunity now, so we're going to see where it takes us."
Martin has been working "heavily" on returning kicks for the past month, Kubiak said, and now he can make that his sole focus, with receiver Lestar Jean healthy again. Jean has missed the last two games following arthroscopic surgery on his left knee last month.
Backup running back Justin Forsett and starting safety Danieal Manning also have experience returning kicks, but Kubiak said Martin is his first choice.
"Hopefully, he can give us a boost, get us going a little bit," Kubiak said.
Notes: Kubiak said RB Ben Tate (toe) practiced on Wednesday and is expected to play on Sunday. Tate sat out Monday night's game. ... S Quintin Demps (left forearm fracture) sat out Wednesday's workout. ... The Texans also signed G Cody White off the practice squad. The 603, 301-pound White is an undrafted rookie out of Illinois State.
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