Rangers' pursuit of a decade of championship domination was severely hampered by a 28thminute goal by Stephen Glass and the second-half dismissal of Lorenzo Amoruso yesterday at Pittodrie.

Now three points behind Celtic with three matches remaining, the Ibrox side looked for most of a rigorous game as though they had emptied their cupboard during the two recent victories over Celtic.

The Rangers manager Walter Smith called the result "disappointing" and said his players had let themselves down in the first half.

"In the second half we picked up without creating any great chances to score," Smith said. "I think the game overall was scrappy and neither team got the ball down and played."

There was a general sluggishness about their play upon which Aberdeen zestfully capitalised. When Amoruso was ordered off in the 59th minute, with the visitors already a goal down, their task became too much.

With Alex Cleland, Gordon Durie, Jonas Thern and Stuart McCall drawing bookings on top of the Amoruso dismissal, it was also a bad day on the disciplinary front for the champions.

That Rangers would have trouble was obvious from early in the game, when Aberdeen demonstrated an energy and commitment that has been missing often enough this season to leave them threatened with relegation. This result leaves them free of anxiety.

By the time Glass produced the goal, the home side were already ahead in thought, movement and execution. They had forced a diving save from Andy Goram, who had to tip away Billy Dodds's left-foot shot after the striker had been released into the left side of the penalty area on Glass's measured pass.

The move which brought the goal was quick and decisive. Mike Newell, returning after a two-month absence because of injury, gathered possession on the left and chipped a pass long to Ricky Gillies on the right.

The young forward saw Glass with only the diminutive McCall for company inside the area and his cross was perfectly delivered. Glass sent the header from 10 yards high to the right of Goram.

Celtic's recovery from the numbing disappointment of defeat by Rangers was impressively quick and complete. Motherwell, potentially harmful visitors to Parkhead, were seen off the premises with a 4-1 defeat.

The Fir Park side led through Steve McMillan after 12 minutes but the way in which Craig Burley and Paul Lambert inspired the home side said as much about their character as it did of their ability.

Burley confirmed the strength of his will, forcing himself into those areas where matches are won. He scored twice before the interval and supplied the passes from which Simon Donnelly completed his double in the second half.