JACKSONVILLE, Fla. -- The ambulance idling next to the practice field was nothing new at the Jacksonville Jaguars' training camp. The attention it received was.

Jaguars players, suffering from the heat, are being rushed off to the hospital at an alarming rate -- three in 13 days of training camp. The latest, receiver Donald Hayes, cramped up at the end of practice Wednesday.

Hayes was treated and released from the hospital Wednesday night. He was back with the team Thursday, but did not practice.

In the past, his symptoms would have been treated on the field or in the training room. But in an era in which teams are ultra-conscious of heat-related problems -- a result of Minnesota Vikings lineman Korey Stringer's death two years ago -- Hayes' treatment took on a more dramatic tone when paramedics and training staff rushed him off the field and into the ambulance.

More than the symptoms, it's the reactions that are putting the Jaguars in the spotlight and raising questions about the kind of camp first-year coach Jack Del Rio is running.

"It's possible that we're on the cautious side," Del Rio said. "I'm OK with that. I know it's going to bring a little more drama and a few more questions, but I can handle that. I'm a big boy. We'll move forward, and we'll keep making sure our players get the best treatment possible."

Players agree that Del Rio's camp has been less demanding than those run by former coach Tom Coughlin. Del Rio schedules two water breaks, one more than in years past. And the Jaguars follow two rigorous periods with one less-intense period designed more for learning and walking through plays.

Given that, a question now cropping up is whether Del Rio, a former player, was demanding enough in his offseason program to compel his players to show up in shape.

The coach criticized 310-pound defensive lineman Larry Smith, the first player to go down, and the only one to lose consciousness. More than a week after he fell, he was still not cleared to participate in all practices. Del Rio said Smith, who was told he had a serious chance to beat out John Henderson for a starting job, "didn't exactly endear himself to the coaching staff" by showing up out of shape.

"We haven't given up on him, or he wouldn't be here anymore," Del Rio said. "So we'll just see. But he's got a long way to go. He's got the talent to get there, but it's up to him to make the commitment."

When Smith and Henderson were taken to the hospital, teammates mostly viewed it as a problem specific to two of the biggest players on the team. The situation with Hayes, who weighs 220 pounds, resonated more deeply.

"It's hard to explain," center Brad Meester said. "I think we're in great shape. We've been to camps that have been much hotter than this. It's two big guys and one little guy and there's no real correlation to anything."

After Wednesday afternoon's workout, J.J. Stokes said receivers were getting more plays because of thin numbers at the position. Jimmy Smith, rookie Cortez Hankton and Matthew Hatchette have all missed time. Del Rio, however, looked at the tape and said Hayes only participated in 19 plays over the 90-minute practice.

"You go back and check yourself," Del Rio said. "You know that things are being done right. So, that's where I'm at."

Hayes was not made available by the Jaguars for interviews.