Gordon Strachan last night confirmed Celtic will need to address their abject away record as a matter of urgency to revive their challenge in Champions League Group E.

A 0-0 draw at home to Aalborg, the minnows of an otherwise illustrious quartet, was a costly start to the campaign for the Clydesdale Bank Premier League champions. Barry Robson missed a penalty and Scott Brown was denied a legitimate second-half goal by an erroneous offside flag.

None the less, Celtic lacked the verve and creativity that has characterised their home form in Europe's elite tournament. They must now rectify their away form - one point from 15 games - in the forthcoming visits to Villarreal, at the end of the month, and Old Trafford on October 21.

To compound matters, the Spanish eked out a draw against Manchester United as Celtic toiled against the Danes.

"We need something from Villarreal, that's for sure," Strachan conceded. "It leaves us with a real challenge now but that's what we are here for. We were below standard in the first half, and of a good standard in the second.

"In the last 45 minutes, we had more territorial advantage and created more chances than any other 45 in the Champions League. We had better movement, better delivery, better chance but we were not at our best in certain areas."

Robson's penalty was saved by Karim Zaza, the inspired Aalborg goalkeeper, after Shaun Maloney was fouled by Steve Olfers. Zaza was in defiant form throughout, denying Georgios Samaras and thwarting a trademark free-kick from Shunsuke Nakamura. "He will be doing all the interviews tonight," said a satisfied Bruce Rioch.

The Aalborg manager was left to lament the performance of Matteo Trefoloni, the Italian referee. He dismissed Michael Beauchamp, the Australian defender, for a foul on Samaras when, in fact, it was committed by Michael Jakobsen, his team-mate. Strachan was more concerned with the flag-happy assistant referee who denied Brown a goal after he was sent clear by Nakamura.

"The goal was onside, I know that for a fact," said Strachan. "The guy who was sent off was not the right guy, either. It was not a great night for the officials but it was not a great night for one or two others, either."

While he refused to reveal the identities of Celtic's prominent felons, Andreas Hinkel's hapless display was a source of deep aggravation. Brown and Robson also struggled to dominate a chaotic midfield. It leaves Celtic with a mountain to climb in search for the nine-point target that could guarantee qualification.

"I am not going to argue with Sir Alex," said Strachan, with the United manager demanding 10 points from his team. "The biggest problem is the result. We now have to try to win away from home."

Rioch, the former Scotland captain, gave his finest Jim Bowen impersonation after confounding the odds again. His post-match media conference was strewn with the adjectives "super", "smashing" and "great".

His delight was understandable as he admitted to fearing for his inexperienced team in a salubrious and unforgiving stage. "They were fantastic, really super," he chirped. "I told them the evening would go by very quickly if they did not get involved. They were all involved and we enjoyed our evening. I told them what they were getting into here. It is a smashing theatre of football and you don't know how players will cope."

Celtic must hope they will prove similarly problematic in El Madrigal and Old Trafford.

"We are not even thinking about what's coming next: Fergie's team," Rioch said, dramatically drawing gulps of air. "We have earned the right to be here. The Danes have their own style: they are cultured and have a mentality of wanting to play football without being overly aggressive."

Aalborg's sportsmanship and all-round niceness would have made Celtic's suffering all the more intolerable for Strachan. Rioch departed with a quip when asked if he was surprised by Celtic's level of achievement. "We played below par here, as well," he smiled. "We did not come here for a draw, or anything else, we came here to play."