Manchester United are facing yet another pitch "problem" as Rostov manager Ivan Daniliants believes the state of the Olimp-2 surface will shock the Europa League favourites.
The United boss called the tie a "bad draw in every aspect" and now has concerns about the state of the pitch in Rostov to contend with.
UEFA has confirmed the home team will train at their nearby training ground rather than at the Olimp-2 in a bid to avoid unnecessary damage to a pitch that Daniliants believes will shock the visitors.
"The pitch is the same for everyone, but it will still be a problem," he said.
"In the final of the League Cup (when they beat Southampton at Wembley), United played on an ideal lawn - it was like a carpet.
"When they arrive here, they will be surprised."
It would not be the first time United have had problems with a pitch since Mourinho's arrival, starting in July when the Bird's Nest quagmire cost them a money-spinning pre-season friendly against Manchester City in Beijing.
In December, the Portuguese was angry with UEFA for making United play their Europa League group-stage decider at Zorya Luhansk on a frozen pitch, with players' studs clacking on the surface the night before the game.