LONDON: Wayne Rooney and Anthony Martial returned to training for Manchester United on Tuesday, though the team could still be hindered by a lengthy injury list as it bids to secure a place in the last 16 of the Champions League against PSV Eindhoven.

The two forwards missed United's 2-1 win over Watford on Saturday Rooney because he was ill and Martial with a foot injury and Marouane Fellaini was also back in training after a calf injury.

But midfielder Michael Carrick will not play against PSV on Wednesday because of an ankle problem, while Ander Herrera and Phil Jones were taken off with hamstring and ankle injuries at Watford. Antonio Valencia and Luke Shaw are also long term absentees.

"We are in a lousy period with a lot of injuries," United manager Louis Van Gaal said.

Elsewhere in Group B, German side Wolfsburg travels to Russia to play CSKA Moscow. Here are some things to know:

DEPAY RESURGENT AT UNITED

Memphis Depay has struggled to reproduce the sparkling form that earned him a move from PSV to United earlier this year, but there are signs he is getting there.

He led United's attack in the absence of Rooney and Martial on Saturday and opened the scoring against Watford with a composed finish.

The 21-year-old Netherlands international believes he is gradually returning to his best from.

"I think every young player goes through things but I keep training," Depay said. "It was important for me to score a goal when I got a chance. I was happy."

United boss Van Gaal, whose team lost against PSV in the opening match in Group B, is expecting another hard encounter.

"It is very important to win, but it is not easy because every game you have to play you cannot say we will beat them," Van Gaal said. "I think that they are a very good team."

PSV EYES KNOCKOUTS

PSV has not qualified for the knockout stages of the Champions League since 2007 but will arrive at Old Trafford with the last 16 firmly in its sights.

Philippe Cocu's side is only a point behind United in second place in Group B on six points, but is level with Wolfsburg.

While PSV's win over United in the Netherlands in September will breed confidence, the Dutch side has not won away in this competition since 2007.

An away victory over United would take PSV to the top of Group B.

WOLFSBURG MISSING

Wolfsburg traveled to Moscow without two important players. Defender Ricardo Rodriguez was left home after the death of his mother. Midfielder Luiz Gustavo is out with a back injury.

Wolfsburg is coming off a 6-0 thrashing of Werder Bremen in the Bundesliga. Germany midfielder Julian Draxler was suspended for the match and may find it hard to return to the starting lineup.

Dieter Hecking's team appears to have improved its defense and the attack underlined its talent, with Germany striker Max Kruse netting twice.

"When we work so well both in the defense and in the attack, we are hard to beat," defender Marcel Schaefer said.

Schaefer is one of the two players still on the team from the 2009 side that failed to progress after losing its last two group matches against CSKA and United.

That's the same schedule Wolfsburg faces now.

PRESSURE RISING FOR CSKA

At the start of this month, all was going well for CSKA, with the Moscow team enjoying a big lead in the Russian league and a solid chance of qualifying from Group B.

Since then, things have turned sour.

A 1-0 loss to Manchester United last time out means CSKA is bottom of the group in the Champions League, sorely needing a win over Wolfsburg on Wednesday in its final home game.

Striker Seydou Doumbia did not play in Saturday's 2-0 loss to Krylya Sovetov Samara due to a lack of fitness, though the club said Monday he was in full training.