McLean High School football coach Karl Buckwalter said yesterday he "was scared to death to go back on the field" after the tragic death of defensive tackle David L. Robinson during the opening day of practice Monday.

In an emotional 45-minute interview at the school, Buckwalter spoke about his close relationship -- on and off the field -- with the 16-year-old, one that began during Robinson's freshman season.

"He was a rare kid," said Buckwalter, a first-year coach, his voice breaking at times. "I was crushed. Dave and I were tight. He would call my house and my wife would answer the phone and know immediately that it was David. I talked about him all the time."

Robinson, a 6-foot-2 1/2, 274-pound junior, collapsed Monday morning while participating in drills. He died after being transported by helicopter to Fairfax Hospital, where further attempts at resuscitation failed. An autopsy performed Tuesday revealed an enlarged heart was the cause of death.

Monday morning's practice began with Buckwalter and his new coaching staff assembling the players for a meeting. After completing exercises and agility drills during a session held in low 80-degree temperatures, Buckwalter said he asked each player how he was doing. "I went up to David and said, 'Big man, you all right? He said, 'No problem, coach, no problem.' "

Buckwalter, a defensive coordinator at McLean the last three years, then ran the players through a conditioning drill he calls "Pride and Perfection." Instead of running straight sprints, the players broke into four groups and ran actual plays. After completing the plays, they sprinted 20 to 30 yards, then jogged back to the starting line to begin the drill again.

"We had student trainers there to squirt water into the players' mouths," Buckwalter said. "The kids like this drill. It's not drudgery and they're still learning."

Robinson had completed his seventh repetition of the drill and was jogging back to his group when he collapsed.

"He just dropped. He just fell. He was face down and still breathing -- I could hear him breathing," Buckwalter said. "I ran to the school and called 911."

Karen Castle, a certified trainer on duty at the practice, and her assistant, Taylor Smallwood, attended to the stricken Robinson. After calling 911, Buckwalter ran to the school's entrance on Davidson Road to direct the ambulance. Then he returned to the field.

"I yelled 'Breathe!' at David, but he didn't breathe," he said.

Soon afterward, a medical helicopter airlifted Robinson to Fairfax Hospital.

Buckwalter said yesterday his team was going through a routine practice and he followed all normal precautions, including frequent rest periods and water breaks.

"It was not meant to be a physical practice, but there was football work to be done. Most of it was mental," he said. "There were plenty of water breaks. When the kids wanted water, they just went and got it. Everything was right, it is right and there's no reason to change it. The kids told us afterward we were doing it right."

The McLean team also practiced the next morning. Buckwalter said he had given some thought to canceling the workout, but he decided it would be best for the team to resume practicing as soon as possible to get their minds off their teammate's death.

Buckwalter said Robinson was determined to improve his game and his physical conditioning this season.

"Last year after we lost to South Lakes, David came up to me and said, 'Coach Buck, I don't want to do this anymore.' He was tired and frustrated, but I told him to hang in there and things would get better for him," Buckwalter said. "When I was hired May 30, one of the first people I went to talk to was big Dave."

About a month later, the school opened a new weight room. Soon after Robinson was there, working out at least three days a week. "David could have gone on to college on a scholarship," Buckwalter said of his co-captain. "He had that kind of potential."

Buckwalter later learned just how much Robinson enjoyed those sessions. When he met with the boy's mother after her son's death, she "shook my hand and said, 'My son loved to come up and work with you,' " he said.

Buckwalter, a 1981 All-Met cornerback from McLean, and Robinson also were close off the field.

"I would be putting the sprinkler out onto the practice field and David would walk with me, put his big arm around me, and we talked about anything," the coach recalled. "We had contests: If he could bench press more than me, I'd buy him a soda. Or if he could bench a certain weight, we'd go out for pizza. It's just a devastating loss to me personally."

Funeral services for Robinson will be held Friday morning at the Second Baptist Church on Annandale Road in Falls Church.