FLORHAM PARK, N.J. - Although Rex Ryan remains adamant that his Jets will resurrect their season, his players are finding it more and more difficult to shake the frustration that comes with a four-game losing streak.

With only days until Peyton Manning and the Broncos (3-1) fly into town, the Jets' latest defeat still eats away at them.

"It's tough,'' slot receiver Jeremy Kerley told Newsday, referring to Sunday's 31-0 loss in San Diego. "It's No. 4 in a row. And you've got guys who are playing hard and busting their butts, so the energy -- it's gone a little bit. So we've got to dig deep, find some way to get it back.

"We've got to go out and prove ourselves week after week, but just with the pressure of four losses in a row, and then you've got an opponent like Denver, it's just tough,'' added Kerley, who has 19 catches for 168 yards and a touchdown. "You've got to climb out of a hole already and then you've got to play an opponent like that.''

Ryan understands his players' frustration over their 1-4 record, but he also wasn't pleased with the way they began practice Wednesday.

"Today we were kind of licking our wounds a little bit,'' Ryan said. "I told our team we've got to get a little more bounce in our step, a little more energy. It was very workmanlike. That's a good thing, but we've got to move past some things and let's get it on.''

But the Jets' slump appears to have shaken their psyche.

"I feel like that's just natural,'' Kerley said, referring to their lack of energy. "When guys are playing hard and playing at a high level, people are going to get fatigued and tired, and then you put a loss on top of that. It's almost like a mental thing.

"If we can get mentally back in it -- which we will -- we'll be all right.''

Geno Smith couldn't pinpoint why guys started practice "a little sluggish'' but said everyone "picked it up'' as it went on.

Yet Ryan remains as optimistic and energetic as ever. He proclaimed Tuesday that this season will be "far from an embarrassment'' in an ESPN New York radio interview.

The question is: Do his players share the same belief?

"I don't know, you'd have to ask them,'' Ryan said. "I believe that this team knows we're going to find a way to get it done and knows that we're going to find a way to win. So I would say so.''

Smith said it "can be dangerous'' when players get down on themselves, but he has "yet to see signs'' of that in the locker room. When asked if his team is "beaten down,'' Ryan denied it, but said he would prefer that his players turn the page on their dismal start.

"As a team we feel like we've let each other down somehow, that we're not where we want to be, certainly,'' Ryan said.

"But I expect that enthusiasm to pick up. I know for a fact that we'll be popping out of our skin to play this one. We're playing Peyton Manning & Co. This is as good as the NFL has to offer, and so who doesn't want to play arguably the best team in the National Football League?''