These are testing times for Jose Mourinho at Manchester United as his side slumped to a third Premier League defeat in their seventh game of the season at the weekend.
Add to that an embarrassing EFL Cup exit to Derby County, as well as reported unrest between the manager and Paul Pogba, and their second game in this year's Champions League becomes all the more significant.
Valencia visit Old Trafford on Tuesday having recorded their first win of the season in La Liga on Saturday and hoping to cause an upset.
Latest odds
Despite their problems, United are clear favourites with bet365 pricing them at 4/6 (1.66) to record their second win in the tournament this season.
Getty ImagesValencia are available at a healthy looking 5/1 (6.00) and United will remember their last home match in the Champions League which saw another Spanish side, Sevilla, win 2-1 and knock them out of the tournament.
The draw, which has occurred in five of the eight meetings between the sides, is offered at 29/10 (3.90).
Team news
Marcos Rojo remains injured for United, while fellow South American Alexis Sanchez is out of favour having not even made the matchday squad against West Ham on Saturday despite reportedly being fit.
Valencia have forward Santi Mina and midfielder Ferran Torres missing, although neither player would have been likely to start.
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Preview
United's recent performances do not inspire much confidence and while they will almost always be favourites at home, there are plenty of reasons to oppose Mourinho's men.
Valencia will be set up perfectly to counter-attack and the speed of Goncalo Guedes and Rodrigo Moreno could be extremely effective.
Los Che will look to improve on their showing against Juventus on matchday one, where they were a little overawed, and the lack of expectation placed on them here means we could see an upset.
Tips and predictions
Valencia/draw on the double chance at 5/4 (2.25) looks to be a highly appealing selection, given United's lack of form.
Marcelino Garcia's side have plenty of attacking strength in Rodrigo, Guedes, Michy Batshuayi and Kevin Gameiro, and they are more than capable of avoiding defeat at Old Trafford.
Prices correct at the time of writing. Please gamble responsibly.
Valencia/Draw double chance at 5/4 (2.25) for a 1.5pt stake with bet365