Umenyiora showed up to the walkthrough portion of practice on Friday morning but left shortly thereafter with swelling in his right knee. Coach Tom Coughlin said earlier in the week that Umenyiora was dealing with "wear and tear" when he sat out Wednesday's practice.
Umenyiora also wore a brace on his right knee during practice Thursday.
Umenyiora had season-ending surgery on his left knee in the 2008 preseason and entered this summer's training camp dealing with residual pain from a torn hip flexor suffered in 2006. If Umenyiora can't go, look for Mathias Kiwanuka to start at right end in his place.
Nicks ran sprints on the sideline during the portion of practice that was open to the media on Friday and said he participated in "a few reps" during practice. Nicks had missed two straight practices prior to rest an ankle injury he suffered in the second quarter against Carolina last Sunday. Nicks stayed in the game and scored three touchdowns in the Giants' season-opening win.
The second-year receiver is optimistic that he'll be on the field against the Colts.
"I expect to play, unless they tell me otherwise when game time gets here," Nicks said after practice Friday. "But [the ankle] felt good today and it's still feeling pretty good, so I feel good about it."
Nicks said swelling in his ankle prohibited him from practicing earlier in the week. But he felt no pain or limitation Friday while running sprints on the sideline.
"Straightaway everything was fine," he said. "Earlier in the week it was just when I would go to the right a little bit. But now I'm going every direction and it feels fine."
"It looks like he's headed in the right direction," Coughlin said. "We'll see how he is in the morning."
If Nicks sits, Mario Manningham likely will start in his place.
Cornerback Aaron Ross says he will play against the Colts Sunday after sitting out Week 1 with a plantar fascia tear in his right foot. Ross participated in three straight practices and pronounced himself ready to go against Peyton Manning and the Colts.
The Giants list Ross as probable.
Ian Begley is a regular contributor to ESPNNewYork.com.