Manchester United - 5, Maccabi Haifa - 2 Audacious as it was, Maccabi Haifa discovered to their cost last night what can happen when a team of greenhorns take the lead at Old Trafford. Manchester United's riposte was an attacking display that will have left the Israeli champions, making their debut in this competition, wondering where they left their L-plates.
By half-time United had overturned the jolt of Yaniv Katan's early strike with goals from Ryan Giggs and Ole Gunnar Solskjaer, and another two at the start of the second half, from Juan Sebastian Veron and Ruud van Nistelrooy, ensured there would be no more hairy moments.
In the end Old Trafford was even treated to Diego Forlan's first competitive goal for the club - in his 27th game - from the spot.
Given United's erratic appearance so far this season, the fact this was their worst start to a league campaign for 13 years and that it had taken them six Premiership games to score the five goals they managed in one half against Spurs last season, this was an opportunity, as much as anything, to soothe their fragile confidence.
Yet there were times when the team making their 81st Champions League appearance were barely distinguishable from the team taking their first, tentative steps in this competition and, after seven minutes, a disbelieving Old Trafford must have wondered whether the unimaginable could happen after all.
Veron had just extracted a fine save from the Haifa goalkeeper Dudu Awate, but United were slow to retreat and, as their opponents counter-attacked with pace and purpose, Walid Badeer threaded a ball between Rio Ferdinand and Mikael Silvestre into the space where Katan was hurtling clear on the overlap.
Old Trafford was hushed into silence as, unchallenged, the striker's diagonal run took him into the penalty area before he despatched a low shot between Fabien Barthez's legs.
For a few seconds there was pandemonium in the corner where Haifa's boisterous supporters were gathered. But United's retort was impressive. Forcing an attack of their own on the right, the ball was worked to Phil Neville, whose cross allowed Giggs to glance a crisp header beyond Awate.
But United had still been given a warning, and Haifa almost embarrassed them again before the half-hour when Katan teed up Nenad Pralija, the one visiting player with Champions League experience, for a volley Barthez was relieved to pluck out of the air.
Most of the attacking thrusts now, however, belonged to the home side. Solskjaer had a shot beaten out, then flashed a header just wide. But when his third opportunity came along he capped a wonderfully fluent move with the finish it deserved.
This time the ball was moved through the middle, first by Veron, again by van Nistelrooy, and Solskjaer was suddenly clear, flicking out his right boot to squeeze his shot past the oncoming Awate.
Had it not been for Awate's fine goalkeeping Ferguson might have been able to relax a little during half-time but, as it was, the narrow margin of United's lead and the nagging feeling that they looked anything but impregnable in defence ensured there was still a slight sense of misgiving.
Within a minute of the second half, however, any lingering nerves had been eased. David Beckham, always a willing outlet on the right, whipped in a low ball that flicked off Solskjaer and bounced nicely for Veron as he ran unmarked into the area.
The angle made it more natural for him to strike with his left foot, but Veron found the combination of power and precision with his right, scoring his first goal of the season.
Van Nistelrooy quickly added a fourth, controlling Veron's pass on his chest, despite the proximity of several defenders, before prodding a bouncing ball past Awate.
Such was United's domination Ferguson brought on Ricardo for his debut in place of Barthez. Forlan also came on but, just as had been the case in his previous 26 appearances, he seldom looked like knowing the difference between a barn door and the goal - until his penalty opportunity, which followed Haifa's second strike, the substitute Rafi Cohen claiming the distinction.
Meanwhile, in the other match in Group F, Olympiakos thrashed last year's finalists Bayer Leverkusen 6-2, helped by a hat-trick from Predrag Djordjevic.
Leverkusen were gifted the lead after 22 minutes as Olympiakos' goalkeeper Dimitris Eleftheropoulos scooped a Bernd Schneider cross into his own goal.
MAN UTD: Barthez (Ricardo 67), O'Shea, Blanc, Ferdinand, Silvestre, Beckham, Veron, Phil Neville, Giggs (Forlan 56), van Nistelrooy (Pugh 75), Solskjaer. Subs Not Used: Gary Neville, May, Chadwick, Stewart. Goals: Giggs 10, Solskjaer 35, Veron 46, van Nistelrooy 54, Forlan 89 pen.
MACCABI HAIFA: Awat, Harazi (Cohen 73), Benado, Ejiofor, Keisi, Almoshnino (Zano 56), Badir, Pralija, Rosso, Zandberg (Israilevich 64), Katan. Subs Not Used: Al Madon, Levy, Gabrin, Nagar. Booked: Rosso. Goals: Katan 8, Cohen 85.
Referee: P Allaerts (Belgium).
