Giants' Mario Manningham still out

EAST RUTHERFORD, N.J. -- New York Giants wide receiver Mario Manningham was not inside the team's practice bubble during the 30-minute portion of Friday's session open to the media and has been listed as doubtful for Sunday's game in Philadelphia.

Manningham, who suffered a concussion Monday night against St. Louis, has undergone a battery of tests but has yet to be cleared to return to practice.

Given that he hasn't practiced all week, Manningham likely won't play, though he has been participating in meetings with the team.

"He's actually doing another test even as you speak," coach Tom Coughlin said Friday. "It's the protocol, you've gotta get by all these things."

Coughlin said he believed Manningham was visiting with a third-party neurologist, who needs to clear the wide receiver before he can return to practice, as mandated by NFL rules. Michael Vick, who also suffered a concussion, was cleared by a third-party neurologist before returning to practice this week.

It was believed that Manningham suffered the concussion during the first half against the Rams. He has not been available to the media this week.

Also missing at practice Friday was defensive end Justin Tuck who was excused because of a death in the family, Coughlin said. The coach said Tuck will play Sunday.

Defensive end Osi Umenyiora, who is recovering from knee surgery, has been ruled out for Sunday. He rode the exercise bike Friday but did not participate in practice.

Rookie cornerback Prince Amukamara (foot) participated in running drills on the team's outdoor track but he has been ruled out as well.

Center David Baas (lower leg) returned to practice after being limited Thursday, while defensive tackle Jimmy Kennedy (knee), who missed Thursday's practice, also was back Friday.

Coughlin said both Baas and Kennedy are "good to go," and Baas told reporters, "I'm fine."

Tight end Travis Beckum (hamstring) practiced for the third straight day. He was limited Wednesday but was fully active Thursday.

Baas, Kennedy and Beckum were all listed as probable.

In two games for the Giants this season, the 25-year-old Manningham has seven receptions for 105 yards. Last season, the fourth-year pro set career-highs in receptions (60), receiving yards (944) and touchdowns (nine).

Coughlin said that if Manningham is out, Brandon Stokley, Victor Cruz, Jerrel Jernigan and Devin Thomas all will be asked to step up.

Jernigan, a rookie, has yet to dress this season, but might get on the field, what with Domenik Hixon (knee) already out and Mannigham potentially unable to play.

"Everybody has to step up because we will have a role for each of them," offensive coordinator Kevin Gilbride said Thursday. "None of them can do all the things Mario does, but each of them can do some of the things he does. We will ask things of those individuals to do what they are capable of doing."

Cruz took reps with the first team on the outside Friday opposite starter Hakeem Nicks.

"I'm preparing as though I'm the starter," Cruz said.

Also, the Giants signed veteran receiver Michael Clayton.

"We just thought that it was better for us to have a little extra security at that spot in case we need it," Coughlin said.

Mike Mazzeo is a frequent contributor to ESPNNewYork.com.