Manchester United are considering a move for Aymeric Laporte, although the Athletic Bilbao defender’s €42m (£30.3m) buyout clause could prove a stumbling block.

The 20-year-old Frenchman is being monitored by Louis van Gaal as the manager targets two centre-halves in the summer, the Dutchman having only three frontline players in the position, Chris Smalling, Jonny Evans and Phil Jones.

While the centre-backs Paddy McNair, 19, and Tyler Blackett, 20, have both made their debuts this season and have signed new long-term deals, Laporte is already an established first-team player for Bilbao. His impressive displays caused the Basque side to raise his release clause from €36m to €42m last summer, with this in place until 2017.

United have been interested in the player for a while and, although Laporte has stated previously he is happy at Athletic, the Old Trafford club believe he could be persuaded to consider a move. They may face competition from Manchester City, Arsenal and Real Madrid.

United’s experience of the difficulty of prising Ander Herrera from Athletic last summer means they may hesitate before making a formal bid. The midfielder’s release clause was €36m (£26m) but an offer of that amount was rejected in a show of strength from Athletic to fans. Herrera then bought himself out of his contract.

Athletic’s policy of using only footballers from the Basque region means they have difficulty locating players good enough for the team, and their sound financial footing means they do not have any need to sell. Spanish regulations also state the player has to be the one who pays any release fee, though this is a technicality.The immediate focus for United, however, is on Sunday as they travel to Liverpool. Van Gaal’s side are fourth in the Premier League, two points ahead of Brendan Rodgers’s team, and Ángel Di María is conscious of the significance of the match.

“We are all aware that a number of big games are just around the corner, and the season will be decided by these fixtures,” said the forward, who is available again following suspension. “We know all about these upcoming games and we have been thinking and talking about them for quite some time now. We’ve known that everything would be at stake over this final periodof the season.

“Everyone at the club is 100% confident. We know we want to get back into the Champions League and that we want to be fighting it out. We’ll battle hard right to the end of the season. From what I know of the club, United always fight right to the end and that’s what we’re going to do.”