Of the four English clubs in the group stage of the Champions League, Manchester United's plight is the most precarious. In a season that has trailed and tailed the margins so far, Louis van Gaal's side are involved in a first make or break tie of the season in Germany at VfL Wolfsburg.

The Opposition
VfL Wolfsburg had been unbeaten at their Volkswagen Arena for the last 29 games until Shinji Kagawa scored  for BVB Dortmund over the weekend to end that streak. March 2014 was the last time a visiting side won there.

Despite the German side's indifferent start to the Bundesliga season, they are the best placed side to progress from the water tight Group B. A draw tomorrow evening would see the German side progress to the last 16. By the same token, they could end up third on the night if United get the win they need and PSV beat CSKA Moscow in Eindhoven. Such are the margins.

Having given United more than a game in the reverse fixture at Old Trafford, the Germans will fancy their chances on the night.

Louis van Gaal says he will have someone on the bench updating the staff of the score in the PSV-CSKA game. Unless CSKA race into a secure three goal lead in the first half, United's task on the night will remain to get the win that guarantees safe passage into the last 16.

Talk of a win for United though has to be tempered by their first desperate need which is to score a goal. Indeed, United find themselves in this position because of their failure to score enough. Any goal of any kind against PSV in the last round would have seen United through by Match-Day 6. Thankfully, qualification remains within the club's hands. All that has to be done is win, not draw, a game of football.

The Sub-Plots
Louis van Gaal went with Marouanne Fellaini in attack at the weekend. His culpability infront of goal and Memphis Depay's industry late on could see a role reversal tomorrow. With Lingard and Martial as the other options, there is a solemn lack of experience upfront in the club's biggest game of the season so far.

Bastian Schweinsteiger returns to Germany with United for the first time. A lot of the leadership required will rest on his shoulders. He won't have much to do though if the players match their performance in the reverse fixture. At Old Trafford that day, Memphis, Martial, Mata and Smalling were among a cast of good performers.

The Bottom-Line
The importance of Tuesday's fixture cannot be understated. A drop into the Europa league would go as far as affecting the club's domestic fixture schedule into the new year. There is every chance therefore that when looking back at the season in May, most of what will have transpired by then would stem primarily from the game tomorrow.

United are suddenly out of margin. It's sink or swim time.