EAST RUTHERFORD, N.J. -- Mario Manningham returned to practice on Thursday one day after sitting out due to a concussion he suffered last week against Tennessee and pronounced himself ready to play on Sunday night against the Bears.
Manningham underwent a test Wednesday and was held out of practice. He also took an "imPACT test" on Thursday, which measures the affects and severity of a concussion. Manningham was cleared to practice after the test.
"I'm good, I practiced today. I'm all right, ready to play Sunday," Manningham said after practice on Thursday.
Manningham said he felt "headaches" after taking a hit late in the Giants' 29-10 loss to the Titans last Sunday.
The second-year receiver out of Michigan said he has no history of headaches or concussion symptoms. He said he felt his last headache on Monday.
"I was cool, I just had a little headache," he said. "That's all it was."
Manningham has 14 catches for 238 yards and a touchdown through three games this season.
Also, Shaun O'Hara sat out of Thursday's practice and is likely to miss his second straight game due to injuries to his left ankle and left Achilles. O'Hara hasn't participated in practice since prior to the Giants' Week 2 game in Indianapolis. O'Hara saw a specialist earlier this week about the injury, which he first suffered in training camp. Backup lineman Adam Koets will likely start in place of O'Hara for the second straight week.
"It's getting late in the week. Something very good would have to happen in a short amount of time," Giants coach Tom Coughlin said when asked if O'Hara would be available for the game against Chicago.
Starting linebacker Keith Bulluck also missed practice on Thursday with turf toe. He initially tried to practice but stepped off the field shortly after testing the injury. Bulluck, who has never suffered a turf toe injury in the past, said he hopes to play on Sunday night.
"I think it's great that we play an 8 o'clock game," Bulluck said when asked of his status for the Giants' prime-time game against the Bears. "I've got two and a half more days to heal up so I think I should be out there."
Bulluck said he suffered the injury on the third play of Sunday's loss to the Titans, but played through it. He felt soreness after the game.
In addition to Bulluck, defensive tackle Rocky Bernard missed his second straight practice on Thursday with a back ailment.
Ian Begley is a regular contributor to ESPNNewYork.com.