(CNN) -- Title holders Manchester United are facing a "nightmare" injury crisis in central defense ahead of their Champions League San Siro showdown with Inter Milan on Tuesday.
United manager Alex Ferguson is worried about his lack of defensive cover for the trip to Inter.
Manager Alex Ferguson revealed the extent of the problem of Saturday's 2-1 victory over Blackburn on Saturday which saw Jonny Evans aggravate an ankle problem.
The Northern Ireland international was set to partner Rio Ferdinand for the match against the Italian champions with Serbian international Nemanja Vidic out through suspension while veteran Gary Neville and Wes Brown are both definitely out.
Utility man John O'Shea missed the Blackburn win with a heel injury and remains Ferguson's best hopes of fielding an experienced utility man alongside Ferdinand.
"We've got some injury issues of course and I just hope we can get two center-backs out there on Tuesday," he told Press Association.
"At this moment in time, it's very doubtful. Jonny Evans is unlikely to be playing, he's looking very doubtful and I'm just hoping to have John O'Shea available because we don't have Gary Neville and we don't have Wes Brown.
"We're having a nightmare with defenders this season. Hopefully we can patch it up for Tuesday because this does leave us very, very short."
Ferguson is faced with the prospect of pitching one of twin teenage full-backs Rafael and Fabio Da Silva into action in the Champions League last 16 tie.
Much of the focus will be on the respective managers as Ferguson is squaring up again against his old rival Jose Mourinho, now in charge of the Serie A leaders.
Forrmer Chelsea boss Mourinho has only lost once to Ferguson in 12 previous clashes and famously his then Porto side knocked United out of the competition at the semifinal stage on the way to their triumph in 2004.
But Club World champions United are still on course for all three domestic trophies in England and are favorites to retain the Champions League.
Spanish league leaders Barcelona, rated by many as the main rivals to United, are also in last 16 action on Tuesday at French champions Lyon.
Barca suffered a shock defeat to neighbors Espanyol at the weekend, but Lyon coach Claude Puel is not fooled, telling Press Association that the Catalan giants were the "the best team in the world."
Puel rested key players Karim Benzema, Juninho, Ederson and Fabio Grosso to the bench for their weekend match against Nancy, ahead of tackling the likes of Lionel Messi and Thierry Henry in their crucial home leg.
Other ties on Tuesday see Arsene Wenger's Arsenal take on Roma at the Emirates and fading Primera League side Atletico Madrid at home to Porto, who are on an excellent run in Portugal.
Arsenal will be without new record signing Andrei Arshavin, who is ineligible, and injury victims Cesc Fabregas and Emmanuel Adebayor, but Wenger remains hopeful his side can break out of a run of scoreless draws which have undermined their Premier League campaign.
"I don't believe Roma will come for a goalless draw," he told Press Association.
"They will play in an Italian way, catch us on the break because they know an away goal will give them a good chance. "We will have to have a spot-on defensive performance and score goals against them."
The pick of Wednesday's ties see Liverpool visit Real Madrid with the Premier League side set to call on the services of talisman Steven Gerrard.
The England star has been out for three weeks with a hamstring injury and did not feature in Liverpool's 1-1 draw with Manchester City on Sunday which seriously undermined their English title chances.
But he trained with the squad on Monday and has been included in the party for the away tie in the Bernabeu against revitalized Real who won 6-1 at the weekend to cut Barcelona's advantage in Spain to seven points.
But Real's good form does not impress Manchester United manager Ferguson who reportedly told French paper Le Journal du Dimanche that they had "no chance" of winning the Champions League.
Ferguson, no lover of the Madrid giants after their attempts to sign Cristiano Ronaldo went on: "Their game lacks pace. They have great players like (Gabriel) Heinze, (Fabio) Cannavaro, (Fernando) Gago, but they aren't quick.
"There is (Arjen) Robben, the only one who can give them some rhythm, but he isn't very brave.
"The three English teams -- Chelsea, Liverpool and Arsenal - or Barcelona (are the favorites, along with United)."
Since the interview on February 4, Real have won three league games in a row under new coach Juande Ramos.