By Richard Clarke

Arsenal are revelling in their Champions League adventure this season but their participation in next year's competition suffered a hefty dent at Old Trafford on Sunday.

Second-half strikes from Wayne Rooney and Ji-sung Park consigned Arsène Wenger's side to their first defeat in eight games. They now trail Tottenham, occupiers of the fourth and final qualification place, by five points. Arsenal have six games left this season, their North London neighbours have only five. 

Despite seeing Thierry Henry named on the bench, the visitors began the game displaying the crisp, controlled passing that had characterised their tie-clinching draw at Juventus in midweek. However, by half-time, the home side had the edge and would have been in front if Kolo Toure had not diverted Rooney's shot on to the post two minutes before the break. Television replays suggested the Arsenal defender may have used a hand. 

But Rooney made up for the miss nine minutes after break, netting with a vicious shot from close range. Arsenal replied with energy but the closest they came to an equaliser was when the excellent Emmanuel Adebayor rifled a shot over the bar. But Park's goal ended the contest 12 minutes from time.

This result is undoubtedly a blow but there is still time to recover - but much will now depend on Tottenham's visit to Highbury at the end of the month.  

There was only one point of discussion before kick-off. Why was Henry not starting? The Arsenal striker was on the bench and, it transpired, rested. Robin van Persie replaced him up front. Elsewhere Adebayor returned after being cup-tied in Turin so Jose Antonio Reyes dropped out of the 16. Robert Pires, a substitute on Wednesday, swapped places with Freddie Ljungberg.

Before kick-off, the Manchester weather was an undecided as a punter on Grand National day. Sunshine, rain, snow and hail all come down from the heavens in the hour ahead of the match. By the time game actually got underway it was grey, cold but thankfully dry.

Arsenal had been slick, controlled and confident at Juve in midweek. They started in similar fashion here with Alexander Hleb and Van Persie giving Manchester Untied keeper Edwin van der Sar some early work to do. 

It took the home side 14 minutes to cause Jens Lehmann similar consternation. Even then Ryan Giggs' corner bounced unconverted across the area.

But Manchester United stepped up the pressure midway through the half. In the 21st minute, Giggs' free-kick was met a poor clearing header from Adebayor. Rooney picked it up and let fly from 25 yards, Lehmann flung himself to his right to push the ball wide.

Six minutes later, the former Everton striker grappled his way past Toure on the edge of the area. Despite the narrow angle, he unleashed a low shot that seemed destined for the far corner before Lehmann once more thrust out his left hand to block.  

On the half hour, Gary Neville hooked the ball into the area and Giggs appeared at the far post to nod over the bar. Then Ruud van Nistlerooy got his first glimpse of goal but dragged his shot wide. 

Inbetween those chances, Van Persie created Arsenal's best chance of the half. He let fly from just outside the area with a low shot that was heading just inside the far post before Van der Sar pulled off a fine low save. 

However the real drama would be saved until two minutes before the break. Rooney raced clear but Lehmann managed to get a glove on the ball as the striker attempted to skip around the German keeper. The striker had been pushed wide but still had the only two scrambling defenders between him and the goal. Toure dived full length to block Rooney's shot and manage to divert the ball on to the post and the chance was cleared. 

In the aftermath, Lehmann needed treatment while Rooney was claiming Toure's touch had been made by his hand.

There would be no let-off nine minutes after the interval. Namanja Vidic robbed Van Persie and Mikael Silvestre floated a high, hanging cross to the far post. Rooney pulled away from Philippe Senderos, collected the ball with one touch and sent a rasping drive past Lehmann with another. 

Arsenal's response was urgent. Adebayor cracked a drive over the bar and Eboue sent a low ball across the face of goal but Van Persie could not convert at the far post. 

The change of emphasis made the much more open - and the home side benefited as much as the visitors. Giggs wriggled past Eboue on the left but could not convert and substitute Louis Saha sent a header just over. 

With 20 minutes left, Hleb's corner from the right was clear to Pires outside the area. He fired low into a forest of players and Adebayor could not flick it home at the far post.

By this stage, Henry and Abou Diaby had replaced Fabregas and Van Persie. Soon afterwards, Ljungberg came on at the expense of Hleb. They would have little chance to make an impact.

In the 78th  minute, Rooney found space on the left and, despite Senderos' challenge, crossed low for Park to convert at the far post.  

There was no way back for Arsenal after that.

Arsenal

13
Lehmann
4
Senderos
27
Eboue
4
Toure
4
Fabregas 70
8
Pires
20
Flamini
13
Hleb 73
15
Silva Yellow Card
10
Adebayor
20
Persie 70

Substitutes

1
Poom
20
Djourou
24
Diaby 70
7
Ljungberg 73
12
Henry 70

Manchester United

1
Sar
2
Neville
16
O'Shea Yellow Card
18
Silvestre Yellow Card
15
Vidic Yellow Card
5
Ferdinand
33
Park 83 Goal!
7
Ronaldo
11
Giggs
17
Nistelrooy 62
10
Rooney Goal!

Substitutes

24
Howard
3
Pique
3
Evra 83
5
Brown
25
Saha 62
Copyright 2014 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source Richard Clarke 9 Apr 2006