Valencia failed to take advantage of Cristiano Ronaldo's early red card in losing 2-0 to Juventus on matchday one and could yet regret not cashing in with all three points against a misfiring United side.
And the World Cup victor was substituted by the Special One during the abject 3-1 defeat to West Ham in the Premier League on Saturday.
If they fail to win either of those, United could face a final-game trip to Valencia needing a result to qualify.
And even the fans want Zinedine Zidane to replace Jose Mourinho as the next boss.
"The players tried. They raised the level of their efforts", Mourinho said.
If the Old Trafford crowd are waiting for United to play the...
Working for BT Sport for the City Hoffenheim game this evening, Pablo Zabaleta was in the ideal position to give his take on Jose Mourinho's team as a former Man City legend and a key part of the West Ham team which brushed aside United in such emphatic fashion.
Mourinho returned to that theme when asked about the Old Trafford faithful, who chanted "attack, attack, attack", cheered under-performing Alexis Sanchez's withdrawal and booed at full-time. He knows that getting to the stadium is by no means straightforward, particularly during rush hour.
Shaw has endured a torrid time at United under the Portuguese coach, but this season has finally seem him nail down a regular starting spot at left-back and he is playing on merit.
Mourinho will look to avoid a fifth successive home match without victory when United host Newcastle in Premier League action on Saturday.
When things belatedly got under way, Mourinho's side struggled to stamp their authority on their first Champions League home match since Sevilla inflicted a shock defeat in March.
"I'm not a fan of Mourinho - if he was made of chocolate he would eat himself".