The topic wasn't pleasant, but it was bound to come up Monday in the Boston office of Sports Advisors Group, a company that represents professional athletes. It was the day after Denver Broncos wide receiver Clint Sampson, one of the firm's clients, was knocked unconscious by a head-on collision with Buffalo Bills free safety Don Wilson.

Another client was in the office that day. In 1978, during the preseason, Darryl Stingley, a wide receiver for the New England Patriots, was hit by Oakland Raiders safety Jack Tatum. Now, Stingley is paralyzed from the neck down.

"I brought it up," said Stingley. "I saw the replay Sunday night and, immediately, I thought how ironic it was. He was wearing No. 84, which was my number. It just really sort of made me cringe."

In Miami, Dolphins Coach Don Shula caught a replay of the hit. "It looked like Stingley," he said. And Wilson, as he watched Sampson placed on a stretcher to be airlifted to a hospital, thought of that, too. "I didn't want to be somebody who hurt a guy like that," he told the Denver Post.

As it turns out, Sampson suffered a concussion, loosened teeth and cuts to his lip and tongue. He still is hospitalized in Denver, and will be out "a while," his coach, Dan Reeves, said.

On the day Sampson lay motionless on the Rich Stadium turf, San Diego tight end Kellen Winslow, the leading receiver in the league, severely damaged ligaments in his right knee and may not be able to play again, Detroit running back Billy Sims tore up his right knee and underwent surgery and Redskins center Jeff Bostic suffered damaged ligaments that also required surgery.

They followed Atlanta running back William Andrews (nerve damage in his knee), Miami running back Andra Franklin (knee), Seattle running back Curt Warner (knee) and Atlanta kick returner Billy Johnson (knee). Among many others.

"It just seems like you're hearing about a lot of prominent people," Shula said yesterday over the phone, "especially with the Winslow thing."

The magnitude of the injuries is one thing; the quantity is something else. There actually have been fewer players placed on injured reserve this season than last. After eight weeks of the 1983 season, 90 players were on injured reserve. At that stage this season, there are 81, according to an NFL spokesman.

There are several theories why so many injuries to vitally important players have occurred this season. One is the increasing strength and speed of the players.

"We are getting bigger guys who are running as fast or faster than they did 10-20 years ago," Shula said. "Even the little guys have gotten stronger."

Another is the frequency of passing. "Because the game has opened up so much in the last 10-15 years," Stingley said by phone yesterday, "most teams are throwing more, and each time a pass is thrown, the receiver goes up. And each time the receiver goes up, there is a chance that what happened to me could happen to him."

Others mention artificial turf, especially because of the frequency of knee and ankle injuries. "If the cows can't eat it, I don't want to play on it," said Washington Redskins running back Joe Washington, who got his foot caught on a tackle by the New England defense and injured his knee. "My injury wouldn't have happened if we had tear-away jerseys and it wouldn't have happened if the game was not on AstroTurf."

The Redskins have put 26 players on injured reserve since the beginning of training camp and have 13 on the list now.

"There's no pattern," said Bubba Tyer, the Redskins' head trainer and president of the NFL Trainers Association. "I wish I knew why this is happening. The players have been getting bigger and faster gradually. They're bigger and stronger, but the guys they're hitting are bigger and stronger, so they should be able to ward it off.

"But it does seem to me there are more key injuries and more severe injuries."