"I'm feeling the best I've felt all season, so just excited to get out there and play football," Diehl said Wednesday.
Locklear, who had started 10 of the Giants' first 12 games this season, playing mostly right tackle, suffered a serious knee injury in the Giants' loss to the Redskins on Monday night. Locklear was placed on injured reserve Wednesday, ending his season.
"Unfortunately Sean hurting his knee, that’s a blow to all of us," Diehl said. "He’s a guy that’s worked extremely hard -- he came in here since the offseason, fit right in with our offensive line, and you never want one of your guys to fall and go down. But like I said, I'm ready to step up."
Diehl has been a cornerstone of the Giants' O-line since he was drafted by the team, starting 140 of a possible 144 games from 2003 to 2011. But he has played in just nine games, and started just five, in 2012.
Diehl has missed time with a sprained knee, and a burner in his neck/shoulder. He also had a hard time winning his job back from Locklear, who performed well.
The veteran lineman admitted Thursday that it was tough to watch the action from the sideline. "I've played in so many games, you never want to sit back and be a spectator. ... That’s a role that I'll never get used to," Diehl said. "But when your opportunity comes back, you come back and you come back strong, and most importantly, you play as best as you can."
Quarterback Eli Manning gave Diehl a vote of confidence on Wednesday.
"He's a guy who's been a starting player for us for nine years," Manning said. "Obviously he's been banged up a little bit this year. But he's back, he's healthy, and we feel that our offensive line, our offense shouldn't miss a beat with him out there."