LASK Linz boss Valerien Ismael warned Manchester United against the danger of underestimating his side in the Europa League on Thursday night.
The first leg of the last 16 tie will be played behind closed doors, to guard against the potential spread of the coronavirus.
Ismael, who played for Crystal Palace against United in a 3-0 defeat in 1998, said Ole Gunnar Solskjaer's side will play into the hands of the Austrian league leaders if they take them lightly.
"It's the match of the century for us, but one we have to play without our family and friends present," said Ismael.
"It's a real highlight for us, a real challenge to play against one of the world's biggest teams.
"United are a great team, they have in every position two, three or four players of the same high quality.
"They are very strong, technically and physically, but maybe what is to our advantage is that they underestimate us and the situation, not playing in front of fans, and the fact they don't know us - that could help us."
LASK Linz are set to miss out on around £1million due to the Europa League clash being played behind closed doors.
LASK President Siegmund Gruber is unhappy at having to take the decision, which was made on the orders of the Austrian Government.
The order restricts the number of people allowed at public events to 500.
