"I was just thinking, 'Man, that sucks!' But we've got to keep moving," Montgomery said. "We don't know what's going to happen, but we definitely need everybody that's in this (locker) room to step up."
As it turns out, Cobb appears to have dodged a major injury in Saturday night's 39-26 preseason loss to the Philadelphia Eagles. He sprained his shoulder after coming down hard on his right side while trying to catch a pass and a defender landed on him.
Cobb said after the game he initially thought that he might have hurt his collarbone, but X-rays showed that was not the case.
Still, it's unclear how long Cobb might be out. The Packers were off Sunday and did not have availability with media on Monday. Green Bay holds its last open practice of training camp on Tuesday in preparation for the final preseason game Thursday against New Orleans.
Both Nelson and Cobb were hurt during the Packers' first offensive series in each game.
Cobb almost certainly will miss the final preseason contest. That means even more chances for young receivers being relied upon to fill in for Nelson to make strong impressions.
"I think I did my part. I think I did what was asked of me, and I feel like a lot of the other guys around me did the same thing because I felt like we were moving the ball well on offense," Montgomery said after the game.
Montgomery, a third-round pick out of Stanford, had two catches for 71 yards, including a 52-yarder. If Cobb is ready for the season opener on Sept. 13 against the Bears, Montgomery would likely serve as the team's third receiver behind Cobb and promising second-year player Davante Adams.
The depth chart after those three players will be rounded out after the Saints game.
Against Philadelphia, Myles White had nine catches for 89 yards, including an impressive 20-yard grab on third-and-4 in the third quarter. Setting up near the sideline, White had to reach back across his body to his right to catch a pass from rookie Brett Hundley. Defensive back E.J. Biggers was also whistled for pass interference on the play.
For White, a second-year player, it was the kind of reception that could stick in the minds of coaches as they make roster decisions with cuts looming.
"That's what you're looking for with Myles," McCarthy said. "You talk about a young man that has just busted his butt the whole time he's been here."
Another second-year receiver, 6-foot-3 Jeff Janis, has the size the Packers will miss in the receiving corps without Nelson. Janis has had an inconsistent camp, though he finished with three catches for 72 yards, including a 27-yard touchdown catch.
The Packers could be on the lookout for veteran help at receiver as teams make cuts. The need will be less acute if Cobb doesn't miss time.
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