John Elway's much ballyhooed and eagerly awaited National Football League debut was a flop today, though backup Steve DeBerg came on in relief to pass the Denver Broncos to a 14-10 victory over the Pittsburgh Steelers before a Three Rivers Stadium record crowd of 58,233.

Elway couldn't even play at the end. The Steelers had forced him to depart at halftime with a bruised right elbow, setting the scene for DeBerg to steal the limelight from the first player picked in the 1983 draft.

The Broncos scored the winning touchdown after DeBerg made a critical adjustment in the huddle. It resulted in a two-yard scoring pass to reserve tight end Ron Egloff with 2:54 remaining.

Elway played the first half but completed only one of eight passes for 14 yards, was sacked four times for 26 yards in losses, fumbled away the ball once, was intercepted once and was called once for intentional grounding.

"The stats say I played bad, but I did the best I could and I'm happy about that," he said. "I would have loved to have gone 35 for 35 and thrown for 500 yards, but it didn't happen."

Coach Dan Reeves said DeBerg relieved Elway because of the injury, not because of the rookie's ineffectiveness.

"If John is healthy, he'll start next week against Baltimore," Reeves said. "I wasn't pleased with John's performance today, and neither was he, but it was still only his first game and it was against one of the toughest defensive teams around and he was hurting."

Elway injured his elbow in Denver's final prseason game and aggravated it today. "It wasn't one play that did it," he said. "Every time I hit the ground it was elbows first and it just accumulated. It's the hardness of the AstroTurf that caused it. I guess I'm going to have to learn how to play with elbow pads."

Elway looked like anything but the second coming of Joe Namath, Roger Staubach or Terry Bradshaw, as had been touted. Instead, he looked tentative, often confused and nervous, just like virtually any rookie.

"I was nervous, but I wasn't out of control," he said.

Except for the job they did on Elway, the Steelers had their problems. Playing without Bradshaw, who is on the injured list after offseason elbow surgery, they turned over the ball over seven times. There were four fumbles, two by Franco Harris, and quarterback Cliff Stoudt was intercepted three times.

"We were our own worst enemy," said Coach Chuck Noll.

The Broncos started their winning drive at their 44 following a punt. Third-year running back Sammy Winder, the game's leading rusher with 96 yards on 20 carries, ran five times for 44 yards on the drive, leaving the Broncos with a third and two at the two.

DeBerg had an amplifier in his shoulder pads and a microphone in his helmet because he bruised his larynx last week and was almost without a voice. He was able to communicate--and execute--the winning play.

Reeves sent in a play-action pass, designed to get the ball to either running back Dave Preston or wide receiver Steve Watson. But just before breaking the huddle, DeBerg told Egloff to hold his block, then release into the left flat underneath Preston.

"In the huddle I just told Ron I might need him," said DeBerg. "The game was on the line and I wanted to have one more receiver to consider."

Egloff held his block, then went into the flat, beat linebacker Robin Cole by two steps and scored.

The Steelers' final drive was stopped when Benny Cunningham fumbled and lost the ball at midfield with 21 seconds to play.

DeBerg completed only four of eight passes for 35 yards and was sacked three times as the Broncos were held to one yard, net, passing.

"We kept blowing it on offense, but the defense kept getting it back for us," said Reeves. "We just hung together and our defense won it for us."

Denver took a 7-0 lead Winder's yard run in the second quarter, after Harris fumbled at his 20. The Steelers tied on Harris' four-yard run 68 seconds before halftime. In the 72-yard drive Stoudt completed five of six passes for 62 yards.