Diehl says he'll learn from poor game

David Diehl had one of the worst games of his career on Sunday night, providing little resistance to Dwight Freeney's pursuit of Eli Manning. But the starting left tackle vowed that such a display will not happen again.

"I'm a guy with a lot of pride and a lot on the line," Diehl said Wednesday. "There's nothing I can do to change that game. The only thing I can do is learn from it and make sure that it doesn't happen again. I know as a player I guarantee anything like that won't happen again regardless of what the situation is, the circumstances."

Diehl said he has studied the film of the Colts game for answers to his poor performance.

"The most important thing is for you to stand up, learn from it and move forward," he said. "I think it's just like that for anybody. When things are great you have to be gracious and when things are bad you have to be humble and you have to learn from it."

Boss comes back

After missing a week with a concussion, tight end Kevin Boss was cleared to participate fully in Wednesday's practice. "I'm completely symptom-free," Boss said. "I felt good out there. It felt good to be back."

The Giants certainly missed Boss, perhaps more for his blocking than his receiving. The team had difficulty slowing outside pass rushers Freeney and Robert Mathis on Sunday night.

"I'm hoping I can come in and help us get back to playing the way we know we're capable of playing," Boss said. "It was tough on everyone last week with the noise and the speed of those guys. I'm looking forward to getting back and helping anybody out that I can."

Johnson doubts suicide

D.J. Johnson was a teammate of Kenny McKinley's in Denver and said he isn't buying the idea that the Broncos' wide receiver shot and killed himself on Monday. The Giants cornerback said he used to hang out with McKinley off the field in Denver and speculated that he crossed paths with some unsavory people there. He said when he heard about the incident, his immediate thought was foul play.

"It was just a thought that something happened, that somebody did something fishy," he said.

Arapahoe County Coroner Michael Dobersen said Tuesday that McKinley, 23, died of a gunshot wound to the head and that a preliminary investigation "suggests the wound to be self-inflicted."

Giant steps

Center Shaun O'Hara, suffering from tendinosis in his Achilles and ankle, was in a protective boot Wednesday and did not practice for the Giants. Tom Coughlin said the Giants would assess O'Hara's availability for practices "day by day." . . . Cornerback Aaron Ross (foot) practiced fully . . . Safety Michael Johnson (back) and wide receiver Mario Manningham (illness) did not practice.