On December 11, Bush sprained his medial collateral ligament in his left knee in the Saints' 27–24 overtime loss on the road against the Chicago Bears. Although diagnosed as a sprain, given that it was the same knee he had surgery on earlier in the year – and that the Saints were now out of the playoff picture with only two games left in the 2008 season – Bush was placed on injured reserve, ending his season early for the second year in a row. He finished the season with 404 rushing yards on 106 carries, 440 yards receiving with 52 receptions and nine total touchdowns, playing in ten games.