Mike van der Hoorn says Zlatan Ibrahimovic remains Manchester United's main dangerman regardless of his goalscoring drought as Swansea prepare to lock horns with Jose Mourinho's men.
The Dutchman previously faced Ibrahimovic during his time at Ajax and he has warned his team-mates the experienced attacker is capable of creating something from out of nowhere.
"I have played against him before, he scored to put PSG ahead with a goal from nowhere," Van der Hoorn told the official Swansea website.
"He has that rare quality of scoring when you least expect it. People can be fooled into thinking that he is having a quiet game and then he creates a moment of genius and scores.
"Manchester United have many, many good players but he is one we must do our best to keep quiet on Sunday."
Swansea desperately need a good result after nine games without a win and Van der Hoorn has admitted it has not been an easy start to the season.
"It has been a very difficult start for us. Results have not gone our way and when you are near the bottom positions you find you often do not get the luck or the 50/50 decisions," he added.
"But all that matters right now is getting three points. A win over Manchester United would give the team a lot more confidence, which in turn gives you more freedom in your play."
