The Houston Texans placed Ahman Green on injured reserve Friday, ending the season for the player signed to be their featured running back. Green missed Houston's last three games with a left knee injury that bothered him for months. He rushed for 260 yards on 70 carries this season, less than what the Texans expected when he signed a four-year, $23 million contract in March. Green rushed for 144 yards in Houston's first two wins but then sprained his knee in the loss to Indianapolis on Sept. 23. He's appeared in only four games since, and his best was a 16-carry, 44-yard effort against Jacksonville on Oct. 14. Houston ranks 23rd in rushing in the NFL, averaging 93 yards. Ron Dayne is the Texans' leading rusher, with 601 yards on 155 carries.