Houston Texans' Alfred Blue (44) is stopped by San Francisco 49ers' Chris Borland (50) as Craig Dahl (43) and Chase Thomas (48) close in during the first quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Craig Dahl (43) and Darryl Morris (40) break up a pass play intended for Houston Texans' DeVier Posey (11) during the first quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Colin Kaepernick watches from the sidelines during the first quarter of an NFL football preseason game against the Houston Texans, Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' LaMichael James (23) is stopped by Houston Texans' Andre Hal (38) during the first quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' LaMichael James (23) is stopped by Houston Texans' Andre Hal (38) during the first quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers head coach Jim Harbaugh calls from the sidelines during the first quarter of an NFL football preseason game against the Houston Texans, Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Blaine Gabbert (2) throws against the Houston Texans during the first quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Asante Cleveland (45) runs for a touchdown past Houston Texans' Eddie Pleasant (35) during the second quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Asante Cleveland (45) celebrates with teammate Quinton Patton (11) after he scored a touchdown against the Houston Texans during the second quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Bruce Ellington (3) dives past Houston Texans' Brandon Harris (26) for a touchdown during the second quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Quinton Patton celebrates after teammate Bruce Ellington scored a touchdown against the Houston Texans during the second quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Bruce Ellington (3) dives past Houston Texans' Brandon Harris (26) for a touch down during the second quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/Patric Schneider)

San Francisco 49ers' Bruce Ellington (3) celebrates with teammates after he scored a touchdown against the Houston Texans during the second quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Kassim Osgood (14) makes a catch as he is hit by Houston Texans' Andre Hal (38) during the second quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Glenn Winston (31) runs past Houston Texans' Jason Ankrah (65) during the third quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)

San Francisco 49ers' Chris Borland (50) runs an interception back for a touchdown past Houston Texans' Uzoma Nwachukwu (17) during the third quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/Patric Schneider)

Houston Texans' Andre Hal (38) returns an interception for a touchdown against the San Francisco 49ers during the third quarter of an NFL football preseason game Thursday, Aug. 28, 2014, in Houston. (AP Photo/David J. Phillip)