Ruud van Nistelrooy's late winner gave Manchester United a crucial Champions League win against Benfica.
He turned home from close range with six minutes left after Rio Ferdinand headed on Ryan Giggs' corner.
Giggs had earlier given United a 38th-minute lead with a free-kick that deflected off Simao Sabrosa.
Simao levelled with another set-piece after the break, but Van Nistelrooy struck to lift boss Sir Alex Ferguson's spirits after recent criticism.
Giggs was given only his second start of the season, with Wayne Rooney serving a suspension, while youngster Phil Bardsley came in for the injured Mikael Silvestre.
United were hoping to show signs of a swift recovery from the damaging home defeat against Blackburn - but it was Benfica who made the brighter start.
A mistake by John O'Shea let in Fabrizio Miccoli, but he was off target and then United goalkeeper Edwin van der Sar needed to be alert to block Ricardo Rocha's header.
Bardsley was soon involved further upfield as Van Nistelrooy almost gave United the lead in stunning fashion.
The Dutchman took a pass first time on the edge of the box, then turned instantly to send a right-foot shot crashing off the bar.
But Giggs had better luck when United took the lead seven minutes before the interval, his free-kick inadvertently glancing off Simao past the stranded Moreira after Cristiano Ronaldo had been fouled.
United's good work was undone after 63 minutes, when they paid the price for Alan Smith's senseless foul on Miccoli.
Simao, who almost joined Liverpool in a £10m deal on transfer deadline day, curled a delightful 20-yard free-kick beyond Van der Sar.
Ronaldo almost provided an instant response, seeing a fierce angled drive turned on to the woodwork by Moreira.
Benfica's confidence was growing, and Van der Sar was in action again as he dived to his left to save from the dangerous Simao.
Van Nistelrooy almost set up Paul Scholes, who had been ineffective, but he was denied by a good saving tackle by Luisao.
The prolific Dutchman did the job himself with a crucial strike after 84 minutes, sweeping home from almost on the line after Ferdinand flicked on a Giggs corner.
It gave Van Nistelrooy the remarkable tally of 35 Champions League goals in 39 appearances - and United a vital victory.
Man Utd: Van der Sar, Bardsley, Ferdinand, O'Shea, Richardson, Fletcher, Smith, Scholes, Ronaldo, van Nistelrooy, Giggs.
Subs Not Used: Howard, Park, Miller, Pique, Ebanks-Blake, Rossi, Martin.
Goals: Giggs 39, van Nistelrooy 85.
Benfica: Moreira, Nelson, Luisao, Ricardo Rocha, Leo, Beto (Mantorras 87), Manuel (Geovanni 87), Petit, Simao, Miccoli (Joao Pereira 80), Nuno Gomes.
Subs Not Used: Quim, Anderson, Kariaka, Dos Santos.
Booked: Luisao, Nuno Gomes.
Goals: Simao 59.
Ref: Lubos Michel (Slovakia).