Manchester United [ Images ] will look to Ruud van Nistelrooy [ Images ] to end their Champions League [ Images ] goal drought and put the former European champions back on course for the knockout stages on Tuesday.

United, third in Group D with five points, failed to score in home and away games against Lille [ Images ] and face the prospect of elimination should they lose to Villarreal [ Images ] at Old Trafford.

• Images: Weekend Football Action

Dutch striker Van Nistelrooy, who scored twice against Charlton on Saturday, has scored 38 times in 45 Champions League matches for United. Villarreal, who will qualify with a victory, are without injured former United striker Diego Forlan [ Images ] and Argentine playmaker Juan Roman Riquelme.

Porto, European champions in 1987 and 2004, are also battling to stay in the competition. Defeat at home by Scottish champions Rangers in Group H on Wednesday would end their interest.

Juventus [ Images ] and Bayern Munich [ Images ] are poised to qualify from Group A. Juve would be sure of a place in the last 16 with a draw or win away at Club Bruges while Bayern would also qualify with a victory over Rapid as long as Bruges do not beat Juve.

Unsettled Bayern midfielder Michael Ballack [ Images ] is likely to be absent. The German international has a thigh injury.

Ajax Amsterdam can join Arsenal [ Images ] in qualifying from Group B with a victory at home over Sparta Prague.

Barcelona [ Images ], on a high after crushing Real Madrid [ Images ] 3-0 at the weekend, will seal top spot in Group C with a win over Werder Bremen [ Images ]. Barca, already assured of a place in the knockout stages, are in daunting form having won their last six games in major competitions, scoring 21 goals and only conceding one.