Manchester United's failure to build a commanding lead over Arsenal has left the Champions League holders exposed to a Gunners side rediscovering its attacking flair and cutting edge to deny them a shot at defending their title.
The slender 1-0 lead the Red Devils take to Emirates Stadium is scant reflection of their vibrant supremacy in the first leg of their Champions League semi-final, hitting the target eight times compared to Arsenal's solitary effort.
"I'm frustrated especially because in the first half we created a number of opportunities," said United midfielder Michael Carrick, who provided John O'Shea's first-half goal. "But the 'keeper (Manuel Almunia) pulled off good saves and things didn't go in. On another day we might have scored more.
"We know it will be tough there next week because they are a good side and the last couple of years we haven't had great results there. Hopefully we can turn that record around."
Without a win at Arsenal since 2005, United lost 2-1 on its last trip to north London in November. A repeat of that domestic score, however, would still be enough to guarantee a meeting with Barcelona or Chelsea in the 27 May final.
World player of the year Cristiano Ronaldo cut a forlorn figure on the Old Trafford turf throughout Wednesday's match after being thwarted by Almunia and shackled by the visitors. The Portugal winger, though, remains certain of advancing.
"We didn't let in any goals there and we will get to the final," he said. "We have one more game and we know if we win or draw we will go to the final. It's going to be very difficult, but Manchester have the opportunity to score everywhere.
"I look forward to scoring there (at Arsenal). Manchester are always favorites. We are the defenders of the Champions League and all the players are confident."
If such assuredness had been evident in front of goal, United could now be reserving seats on the plane to Rome next month.
Instead the Premier League rivals, meeting for the first time in Europe, are only separated by O'Shea's 18th-minute goal - the Ireland defender firing into the roof of the net after Carrick's cross deflected off Alex Song.
Alex Ferguson did say before the match that he would have been satisfied with a 1-0 win, but the United manager was left ruing his players for not converting their overwhelming display to a bigger score, enabling a lucky escape for Arsene Wenger's side.
"Arsene will be thinking it has been a good day for him," Ferguson said. "He could have been out of the tie but he is not. We tend to do things the hard way and it was another night when the fans got frustrated, but that's the nature of the club."
While Ferguson believes the maturity of his squad will give it the edge over Wenger's, the youthful Gunners will be fresher Tuesday because they are out of the Premier League title race, which United is on course to win.
With the fourth Champions League spot all-but sealed for Arsenal, Wenger can field a weakened side against Portsmouth on Saturday as the Frenchman looks to end the club's four-year trophy drought.
United, though, can't take any such risks at Middlesbrough as the defending champions cling onto a three-point lead, potentiality without Rio Ferdinand. The center back was sent to a hospital for X-rays after Wednesday's match to determine whether he has a broken rib.
"Arsenal's big advantage is that they can play (assistant manager) Pat Rice at right back and Arsene himself at center forward on Saturday," Ferguson joked. "We have to play a team to win the game. We have a lunchtime kickoff at Middlesbrough and I do not think it is right.
"Obviously I will bring some freshness into the team. The defense will be the same, apart from Rio Ferdinand but the midfield and forwards could change completely."Reuse content