The Facts: With concerns still surrounding the back injury to Chris Brown, the Texans signed Bell on Thursday.

Diehards Line:Bell is well-versed on the zone-blocking scheme the Texans are implementing this offseason. He is a third-year back who saw his most success as a rookie in 2006 in Denver. He posted the fourth-most rushing yards (677) and tied for the second-most rushing touchdowns (8) by an undrafted NFL rookie since the inception of the common draft in 1967. Bell battled injuries in 2007 and saw little playing time. ... For what it's worth, Brown missed his fourth day of practice because of back problems Thursday. HC Gary Kubiak said his return could still be two more days away. Chronicle beat writer John McClain told visitors during an online chat earlier this week that he's not sure Brown will make the final cut.