ENGLEWOOD, Colo. (AP) Danny Trevathan is grappling with a setback in his comeback.
The Denver Broncos' top tackler from last season reinjured his left leg Sunday in his second game back from a broken bone under his kneecap. He learned Monday he'll miss several more weeks with another crack on the top and side of the same kneecap.
Coach John Fox said this latest injury is ''nothing even remotely the same as his last injury.''
However, the timeline for his return might be similar.
Although Fox declined to say how long he expected Trevathan to be out, his teammates mentioned six weeks when talking about the linebacker's latest injury. Trevathan returned in the sixth week after his first knee injury, which occurred on Aug. 12.
Trevathan was able to put weight on his left leg Monday. He walked haltingly through the locker room while holding - but not using - the same crutches he thought he'd ditched for good last month.
The Broncos' weakside linebacker was hurt when he was run over by two New York Jets on a screen pass to Eric Decker on the second play from scrimmage in Denver's 31-17 win at the Meadowlands.
Backup Brandon Marshall switched helmets with Trevathan so he could make the defensive calls, and rookie Corey Nelson slid into Marshall's role on sub packages and led the Broncos with seven tackles.
''Our defense, we never flinch,'' Marshall said. ''So I just came in and I'm like, `Let's go, man.' We live for this.' And that's what I was telling the guys, and we got it done.''
Marshall finished with six tackles, same as strongside linebacker Von Miller. Marshall said he leaned on the experience he gained from filling in for Trevathan the last time.
''It was an easier transition this time,'' Marshall said. ''The Colts game, the first time, I was a little nervous; I'm not going to lie. But when I went back in this game, I think it was a little slower. The game wasn't fast. It slowed down for me, so that was good.''
It slowed down quickly for Nelson, too.
''It's kind of like just getting practice or repetition as a youngster. You've got to get the game-time experience,'' said Nelson, a seventh-round pick from Oklahoma. ''And I felt like as the game went on, I was able to settle my feet and get more comfortable to be able to do what I had to do for the defense.''
Nelson, who played just two snaps on defense before Sunday, finished with 36 snaps from scrimmage and 26 on special teams.
''He knew what he was doing. He didn't blink,'' Marshall said. ''I guess the moment wasn't too big for him. I'm happy for Corey. He did well. He'd been working his tail off. He's going to be a good asset for us.''
Nelson did make one big blunder. He was late getting onto the field after a punt in the second half and the Broncos had to use a timeout.
''I guess he thought it was a different package,'' Marshall said. ''So, I had to call a timeout, because it was an empty set. They were going to pass the ball, and if he wasn't in there, it might have been a touchdown.''
Nelson said he went over to talk with special teams coordinator Jeff Rodgers ''and I just lost track of what personnel was out there. That's on me. I take responsibility for that.''
It was a small blemish in a breakout performance for Nelson, who didn't even think he'd get drafted after tearing his left pectoral midway through his senior season with the Sooners.
''Man, Corey was huge this game,'' cornerback Chris Harris Jr. said. ''He stepped up and played a great game. Nobody knew we were going to have to use him this much this year or in that game. But he's going to have to learn fast with Danny being out six weeks. We're going to need Corey to step up.
''We're going to need him to improve because it's only going to get tougher. We're going to face better offenses than that.''
NOTES: Coach John Fox disputed several of the Broncos' 11 flags from Sunday. ''We turned in a lot of them'' to the league office, he said. ''I can't really talk about the specifics. But that's not absolving any blame for us, either.''
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