SAN DIEGO (AP) Whoever snaps the ball to Philip Rivers on Sunday at Oakland will be the fourth center to start for the San Diego Chargers in six games.
Will it be Chris Watt, the rookie guard from Notre Dame whose four plays on Sunday were his first at center in a game that counted at any level? Or Trevor Robinson, who will be signed off the Cincinnati Bengals' practice squad? Or will Rich Ohrnberger's back injury have cleared up by then?
Coach Mike McCoy left that decision up in the air Monday after announcing that Doug Legursky will be placed on injured reserve, the second center lost for the season in a span of five games.
''There'll be one out there on Sunday,'' McCoy said. ''I'm not going to give a drop-down list of who could possibly play. We work a bunch of them. We're going to play the healthiest guy who helps us win.''
Odds are it'll be Watt, who came in Sunday after Legursky went down with a knee injury in a 31-0 victory against the New York Jets. Watt was in for four snaps in his first regular-season action at the position.
''I'll be ready to go,'' said Watt, who got experience at center during the exhibition season. ''I've been preparing for it in the preseason, all offseason. It's got to be the next-man-up mentality. Got to be ready to roll.''
Watt said there were a ''couple things I could do better. But overall there wasn't too much that was being shown, the last few plays of the game. It was fairly easy to pick up. I thought I did a good job.''
Watt and Robinson were teammates at Notre Dame.
''Trevor's a great guy. I talked to him last night. He wasn't sure yet if he'd be here or not but this morning he was pretty excited to be coming out here,'' Watt said. ''He's one of my friends, one of the guys I played with for a few years on the offensive line at Notre Dame, so it's going to be interesting to have him back here.''
The Chargers (4-1) lost veteran center Nick Hardwick to a neck stinger in a season-opening loss at Arizona.
Ohrnberger replaced Hardwick in the opener, made two starts and then missed the last two games with a back injury.
Asked if he'll play Sunday, Ohrnberger said: ''You know I can't answer that question. I'd love to, but ... I guess the stock answer is I'm doing what I can to get out there. There's improvement every day. Obviously with any injury the more you're working it, the better you're feeling. So it's heading in the right direction. I'm just trying to get out there as soon as possible.''
Ohrnberger clearly has been indoctrinated by McCoy's distaste for discussing injuries.
Asked if he's been able to do any football activities, Ohrnberger said: ''Every day brings new challenges so we'll see what tomorrow brings.''
Ohrnberger did say that losing Legursky was ''a huge bummer. Obviously every season you're going to have injuries, but I mean, they're coming fast and furious right now. We're all hoping that things slow down a little bit on that front. `'
McCoy said the Chargers have a number of players who can snap the ball but declined to name them.
Asked if he has confidence Watt can get through a full game at center, the coach said: ''I've got a lot of confidence in our entire roster just like I have every week here. We've got a lot of depth and this is why we practice the way we do. We move guys around for reasons like this.''
Asked about Ohrnberger, McCoy said: "We've got a great idea when he's coming back. We're not going to make any predictions. We're not going to report anything on surgeries, no rehab. The players will all be out there when they're healthy and they're going to help us win.''
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