Louis van Gaal will assess the 21-year-old Bolton left-back Andy Kellett during his surprise loan spell at Old Trafford before making a decision on the player’s possible long-term future at the club.

United had been monitoring the defender for several months before making the move to sign him on transfer deadline day – a call which Kellett initially thought was a “wind-up”.

The defender made only his first Wanderers appearance of the season last Tuesday, in a 4-2 defeat to Rotherham, having previously been on loan at League Two Plymouth Argyle – where he attracted attention with a brilliant solo goal in December.

Van Gaal had targeted Borussia Dortmund’s World Cup-winning defender Mats Hummels so to finish deadline day with only the late acquisition of Kellett was unexpected. He made the decision to move for the player when Bolton’s manager Neil Lennon made an inquiry about taking Saidy Janko from United on loan.

“It’s a great opportunity for Andy,” said Lennon. “We called about Saidy and Manchester United asked for him to go the other way. He thought it was a wind-up.

“He hadn’t got a clue. He was on his way to Plymouth. It took a good five or 10 minutes – he wouldn’t believe us. We told him to ring his father and we’d tell him, and once that happened I think it started to sink in. It’s a great story but now he’s got to knuckle down and learn.

“It’s great for the kid. It’s an opportunity for him regardless of what happens. He’s no bother, low maintenance, very level-headed and I just hope he takes it in his stride.”