Manchester United boss Louis van Gaal expects to face a motivated Arsenal after their defeat to Olympiakos.

Van Gaal expects a response from Arsenal following their European disappointment but he warned Arsene Wenger to do better with the players at his disposal.

"We are happy but I think Arsenal can come back from a defeat," the United boss said. "They have shown that a lot of times.

"Arsenal are technically and tactically the best team in the league. Nevertheless, they haven't won so much, so you have to look for that improvement with that team."