Robin van Persie's brace saw Manchester United through to a 2-1 win at CFR Cluj-Napoca in their Champions League Group H clash at the Dr. Constantin Radulescu Stadium.
After an opening quarter of an hour in which United completely dominated possession, Cluj hit them on the break with ruthless efficiency to take the lead via Pantelis Kapetanos.
The home side were well set up to defend and hit United on the counter-attack, and it took a moment of good fortune for Van Persie to score United's equaliser on the half-hour mark.
The Dutchman then scored the seventh goal of his eight-match old United career early in the second half, as his new team made much easier work of their task after the break, although David de Gea was called into action in injury time to make sure Alex Ferguson's side returned home with the victory.
Both of United's goals were set up by Wayne Rooney, who started a match alongside Van Persie for the first time.
The win sends United top of the group with two wins from two following their win over Galatasaray two weeks previously. Cluj remain second on goal difference.
Follow Saturday's 3-2 defeat at home to Tottenham – the first time they had suffered a league defeat at Old Trafford to the Londoners in 23 years – United manager Alex Ferguson seemed intent on taking it out on the Romanian champions.
To that end, he started Van Persie and Rooney together for the first time in a line-up that also included Javier Hernandez.
However, for all of their early possession orchestrated by a deep-lying Rooney and Tom Cleverley, once again it was in defence where questions will be asked of United.
With Nemanja Vidic the most notable of several long-term absentees at the back, the pairing of Rio Ferdinand and Jonny Evans again conceded early.
Rafael Bastos, whose two goals gave Cluj victory at Braga on Matchday One, pinged an excellent ball out to Modou Sougou on the right wing. The Senegal forward found it all too easy to make space off Patrice Evra to cross, and his pulled-back pass into the area was swept past De Gea first time by Kapetanos. It was the Greek's seventh goal of the season in all competitions, a run which included the decisive goal in Cluj's play-off against Basel.
Evra was relieved to see Sougou substituted due to injury after just 24 minutes as United resumed their hogging of more than 70 per cent of the first-half possession. Rooney forced a save from goalkeeper Mario Felgueiras before Van Persie fired Cleverley's through ball wide on the turn as the Red Devils began to put the pressure on once more.
For all their possession and enterprise it took a big slice of fortune to give United their equaliser. Hernandez was fouled out on the left, and Rooney's free-kick was met by Van Persie with his back to goal. The former Arsenal striker tried to glance a header on goal, but mistimed his jump and instead the ball bounced off his shoulder and looped over the helpless Mario Felgueiras in the Cluj goal.
United made the most of that leveller when, just three minutes after half-time, Van Persie got a second goal. Again it was Rooney who floated a ball into the box down the right channel. Felgueiras was too slow off his line and Van Persie's well-timed run allowed him to meet the ball first and casually knock it past the keeper into the unguarded net.
Just as with his hat-trick in the 3-2 win at Southampton and his winner from the penalty spot at Anfield, Van Persie's goals once again proved to be winners for United as they closed out the match in dominant style, for the most part.
Rooney, Anderson and cleverly in particular were instrumental in starving Cluj of the ball, and United boss felt confident enough in his team's position to give young Scott Wootton a European debut with 11 minutes remaining. The defender replaced Evans, who appeared to be struggled with a knock for much of the second half.
Cluj captain Ricardo Cadu had earlier forced De Gea into tipping his header from a corner over the bar, and the Spanish keeper was once again equal to an aerial assault when, in stoppage time, he parried Bastos's header at the near post.
The performance was at times unconvincing, but the win was just what United needed ahead of this weekend's trip to face Newcastle United.
MAN OF THE MATCH – Robin van Persie (Manchester United): The Dutchman is already making a habit of claiming victories for United, and his brace did that once again.
CFR CLUJ: Mario Felgueiras 6, Ivo Pinto 6, Sepsi 6, Cadu 6, Rada 6, Camora 6, Muresan 6, Rafael Bastos 7, Aguirregaray 6, Kapetanos 6, Sougou 7. Subs: Luis Alberto 6, Bjelanovic 6, Nicoara N/A.
MANCHESTER UNITED: De Gea 6, Rafael 6, Ferdinand 6, Evans 5, Evra 5, Anderson 7, Fletcher 7, Cleverley 7, Rooney 7, Hernandez 6, Van Persie 8. Subs: Wootton N/A, Welbeck N/A.