Iupati injured his left ankle on a one-yard touchdown run by 49ers fullback Anthony Dixon to give San Francisco a 10-0 lead over the Seattle Seahawks in the second quarter of the NFC Championship Game. Iupati had to be helped off the field and couldn't put weight on his ankle. He was later carted off the field.
He was replaced by Adam Snyder, who started four games this season and played well when Iupati suffered a sprained MCL Nov. 17 at New Orleans.
James was on his back on the field for several minutes before being helped to the sideline with his arms around trainers.
James had attempted to field the punt from Seattle's Jon Ryan on the first play of the second quarter, but the ball hit off his chest. As he attempted to reach for the ball, Lockette hit James hard to the turf.
The 49ers announced James was questionable, but he returned to the field a kickoff later in the second quarter.
Information from The Associated Press was used in this report.