Then came the explanation. It was accompanied by flashing lights. The ambulance was for Chris Clemons, the Eagles' new defensive end.

An hour earlier, Clemons had been driven off of the practice field on a cart, a victim of dehydration. He was impaired enough that it took a couple of trainers to support him out of the vehicle and into the fieldhouse. It was a hot day, and there had been more hitting at practice, and the ranks had already been thinned along the defensive line because of injuries, and it was too much for the free agent acquisition from Oakland.

"He wasn't as responsive as we liked," said Rick Burkholder, the Eagles' head trainer. "He wasn't unconscious . . . he was conscious through the whole event. He just wasn't responding to our questioning the way we liked and in those situations, my staff, we err on the side of caution. We get those guys to a place where they have advanced life support in case anything would go wrong.

"I don't think, at any time, we felt like his life was in danger . . . or anything like that," he added.

By about 6:30 last night, Clemons had been released from Lehigh Valley Hospital and was back at camp. He had been given fluids intravenously and also given a CT-scan to rule out a concussion. Burkholder said Clemons could possibly be practicing again in a couple of days.

Worst nightmare over, then - and that is exactly what dehydration is in the modern NFL, the absolute worst nightmare for a training staff. Especially since the death of the Minnesota Vikings' Korey Stringer, 7 years ago, the league has become much more conscious of keeping 300-pound athletes cool enough and hydrated enough during the rigors of summer camp.

Camps are easier now, even tough camps like Andy Reid's. The truth is that the Eagles go to significant lengths to try to avoid what happened to Clemons.

"I think there is an adjustment period for new players to our system," Burkholder said. " . . . I think this is a tough, tough thing that we do here and we try to be very proactive with it. Sometimes we come up short. Today, we came up short. But we'll bounce back with him. I'm going to make sure it doesn't happen again with him."

If you ever get close enough to the practice field, you will see several trainers whose only job during practice is to get right behind a specified list of players and point what looks like a television remote control at the small of their back. What it does is measure the player's internal body temperature, reading a tiny sensor that the player swallowed the night before.

Every player's temperature is not measured every day on the field. Two defensive linemen were measured yesterday but Clemons was not one of them. But, Burkholder said, "Chris will be in that group now."

The attention to detail goes beyond internal thermometers, though. This is a sport that used to laugh about players passing out at practice, that took it as a demonstration of weakness. (And it wasn't that long ago.) Giving players Pedialyte, the electrolyte drink made for infants, was considered cutting-edge science. Now, well, listen to Burkholder:

"I have a team of people in this training camp, that are athletic trainers, that do nothing but dehydration research. We study these guys, we draw blood on them, we collect urine, we collect sweat, we try to match up drinks with their body type and how they give off electrolytes.

"Chris is a new player to us. We're not matched up with him yet. On top of that, we had three or four defensive linemen out this morning at the last minute and so the numbers game got to him. It caught up to him."

When a player goes down from the heat, the first part of the Eagles' protocol is to get him off of the field and into the fieldhouse as quickly as possible. Then, as an IV is started, the player puts on a cooling vest and a cooling cap to try to get his body temperature down. Burkholder said that Clemons went through all of that and was observed by a physician the whole time.

"Chances are, he could have come around with the IV and we would have been all right inside," Burkholder said. "I just felt like, if he didn't do that, I don't have the advanced life support that those guys have at Lehigh Valley Hospital."

So what do you do?

"We call 911 and we tell them that we're the Philadelphia Eagles, and they're like everybody else - they show up," Burkholder said.

He laughed. He said the same thing had happened to a player last year but nobody knew about it because there were no reporters around. Yesterday, the pace with which Clemons was loaded into the ambulance and driven away to the hospital was not frantic, not nearly. The suggestion was of urgency but not emergency.

These were professional people being professionally cautious. With all of the science, there is still a human element.

"This is not my ego, but I have a feel," Burkholder said. "I've been in the league for 15 years and you know that when you look at a player and he doesn't look back at you and can't answer your questions, that it's not normal.

"These guys, they communicate very well with me because I have to take care of them. When they don't communicate, you know there's something up. Here's a guy who knows that he's in trouble and can't answer my questions, you don't worry about blood pressure, you don't worry about any of that. At that point you say, 'Let's go. We're gone.' "

And they were. Seven hours later, Chris Clemons was back at Lehigh. The plan was for him to attend his evening position meeting. *

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