Manchester United could be without defender Rio Ferdinand while AS Roma will definitely be without striker Francesco Totti when the teams meet in the second leg of their Champions League quarter-final on Wednesday.
Roma, 2-0 down from the first leg in Italy last week, were hoping club captain Totti might recover from the thigh strain that kept him out of that match but, despite conflicting reports about his fitness, they travelled to England without him.
Mirko Vucinic, who scored with a superb dipping shot from 20 metres out in Saturday's 3-2 win over Genoa in Serie A at the weekend, will lead Roma's attack in his absence.
With United favourites to qualify, manager Alex Ferguson might rest Ferdinand after he was injured in Sunday's 2-2 Premier League draw at Middlesbrough.
Ferguson had feared the worst after watching the England defender limp off in the second half but a scan on Monday revealed he had not broken a bone in his foot, although United's medical staff did not say how long he might be out of action.
Having already lost Ferdinand's defensive partner Nemanja Vidic for at least two weeks, a serious injury to Ferdinand was the last thing Ferguson needed.
MAJOR SHOCK
Despite United's worries at the back, it would be a major shock if they failed to advance. A year ago this week, at the same stage of the competition, United demolished Roma 7-1 at Old Trafford and the English side have never lost a home match in Europe by more than the two goals Roma require to advance.
They also beat Roma 1-0 at Old Trafford in the group stage in October this season and have not lost at home in Europe for three years.
Italy midfielder Alberto Aquilani is in Roma's squad but is a doubt after missing the Genoa game with a foot problem, while defender Matteo Ferrari is out with a knee injury.
Despite all that, Brazilian winger Rodrigo Taddei is optimistic about Roma's chances of reversing the first-leg defeat.
"I'm sure that if we play our best we can go to Old Trafford and reach the semi-finals," Taddei, who missed last year's 7-1 drubbing after straining a muscle in the warm-up, told Sky Italia television.
"We know that it will be very difficult, but there are still 90 minutes to go and we'll play them all. Apart from the night of the seven goals, the games have always been evenly balanced between us."
Roma regain midfielder Simone Perrotta from suspension and Brazilian defender Juan should be back in the starting line-up after returning from an ankle injury to come on as a substitute against Genoa.
One intriguing aspect of the game will be the performance of Cristiano Ronaldo, who was accused by Roma's David Pizarro of using his skills to mock Roma in the first leg.
Taddei tried to diffuse the situation by saying: "As a Brazilian I understand Ronaldo. He does those moves even when the score is level.
"It's true that sometimes he goes too far, but football is a spectacle. With Wayne Rooney he is part of the best strike partnership in the world, they are showing this week after week in the Premier League."
Possible teams:
Manchester United: 1-Edwin Van der Sar; 3-Patrice Evra, 6-Wes Brown, 19-Gerard Pique, 22-John O'Shea; 18-Paul Scholes, 16-Michael Carrick, 17-Nani, 11-Ryan Giggs; 10-Wayne Rooney, 7-Cristiano Ronaldo
AS Roma: 32-Doni; 2-Christian Panucci, 5-Philippe Mexes, 4-Juan, 22-Max Tonetto; 11-Rodrigo Taddei, 7-David Pizarro, 16-Daniele De Rossi, 20-Simone Perrotta, 30 Mancini; 9-Mirko Vucinic.
Referee: Tom Henning Ovrebo (Norway)
