Manchester United will need to put a string of injuries, a ban for top striker Wayne Rooney and a weekend upset firmly behind them in Tuesday's Champions League game against Benfica.
United, who started their Group D campaign with a 0-0 draw away to Villarreal, will need to dig deep at Old Trafford after little has gone right for Alex Ferguson's side.
Injuries have left Ferguson without three defenders, Gary Neville, Wes Brown and Gabriel Heinze, two midfielders in skipper Roy Keane and Quinton Fortune and two strikers, Louis Saha and Ole Gunnar Solskjaer.
But Rooney's absence for a red card in Spain two weeks' ago, having sarcastically applauded referee Kim Milton Nielsen for a second yellow, will be the biggest blow of the lot.
The 19-year-old was United's top scorer last season, notching a memorable Champions League hat-trick on his debut against Fenerbahce, and his penetrating runs remain United's deadliest weapon.
His sheer drive set up Ruud van Nistelrooy's second-half equaliser against Blackburn Rovers on Saturday, having come on as a substitute in what turned into an embarrassing 2-1 defeat at Old Trafford.
Ferguson blamed missed chances for the loss and said it had set his men a test for the games ahead.
"It was a hiccup, there's no question about that," he said. "In the past we've shown that we do well in adversity. Well, that's the test now."
Benfica, who opened their campaign with a 1-0 home win over Lille, will look to striker Nuno Gomes to cause United trouble after scoring five goals in his last two domestic league games.
"I am in good form, so the goals will continue coming," he said after Benfica beat Penafiel 3-1 on Friday.
Dutch coach Ronald Koeman declared that the club's poor start to the season was over.
"We have won the last three games and that's raised morale," said Koeman. "Against United it will not be enough to defend well, we need to attack and get a goal. Winning would be a great result, but drawing away would be good."
Tuesday's match will renew an old rivalry in European football.
United became the first English club to win the European Cup when Bobby Charlton steered them to a 4-1 victory over the Portuguese side after extra time at Wembley in 1968.
They first met in the 1966 quarter-finals, with United shading the first leg 3-2 at Old Trafford before going on to record a famous 5-1 victory in Lisbon.
Probable teams:
United: 19-Edwin van der Sar, 22-John O'Shea, 5-Rio Ferdinand, 27-Mikael Silvestre, 23-Kieran Richardson, 11-Ryan Giggs, 24-Darren Fletcher, 18-Paul Scholes, 7- Cristiano Ronaldo, 10- Ruud van Nistelrooy, 14-Alan Smith.
Benfica: 1- Moreira, 22-Nelson, 4-Luisao, 3-Anderson, 5-Leo; 6-Armando Petit, 14-Manuel Fernandes, 16-Beto, 20-Simao Sabrosa, 30- Fabrizio Miccoli, 21-Nuno Gomes.