Man Utd will lose one of their top young prospects this summer after contract offer rejected

One of Manchester United's top young prospects has said his farewells to the club and has reportedly agreed to join La Liga side Athletic Bilbao.

United's pre-season campaign got underway on Saturday afternoon, with a relatively young squad taking on Wrexham in Helsinki.

With many players absent due to their participation in this summer's World Cup - a four-week break is mandated after elimination from the tournament - the early stages of pre-season will be a good opportunity for younger players to stake their claim for a spot in Michael Carrick's first team.

The goalkeeping department was represented in Helsinki by the heavily-experienced Tom Heaton, along with academy graduates Dermot Mee and Radek Vitek.

New signing Karl Darlow is still recovering from a 'procedure' he had at the end of last season, while Senne Lammens has been on World Cup duty with Belgium.

One youngster who was not part of the travelling squad is 16-year-old Darlington Osuchukwu, who is set to seal a move away from Old Trafford this summer.

The goalkeeper joined United as a 13-year-old and has progressed through their ranks. He played for Spain U17 earlier this year after previously representing England at youth level.

Osuchukwu has played for both England and, most recently, Spain at international youth levels (Image: Getty)

But he will now return to the country of his birth.

Journalist Pete O'Rourke reported in June that Osuchukwu, who is said to have been highly thought of within the United youth ranks, was being targeted by La Liga champions Barcelona.

But it is Bilbao who have won the race to sign him, it has been reported - with the goalkeeper penning a farewell message to United on Instagram.

'Impossible to put into words' - Goalkeeper pays tribute to Man Utd

Osuchukwu wrote that he had made the 'incredibly difficult decision to move on' from Old Trafford, revealing that the club had made attempts to keep him.

"This was not a decision my family and I took lightly. While I was grateful to be given the opportunity to continue my journey here, we believe the time is right to begin a new chapter," he stated.

"It is impossible to put into words how much this club has meant to me. I want to thank everyone at Manchester United - and I truly mean everyone. From the coaches who believed in me, to the kitmen who worked tirelessly behind the scenes, and especially my team-mates, who became so much more than team-mates - they became my brothers.

"Every one of you has played a part in shaping not only the footballer I am today, but also the person I have become. The lessons, values, friendships and memories I have gained here will stay with me for the rest of my life.

"I also want to thank the club for believing in me and giving me the opportunity to wear this badge. Representing Manchester United has been one of the greatest privileges of my young career, and something I will always be proud of."

Spanish outlet AS report that United had 'no intention' of allowing the goalkeeper to leave, but that Osuchukwu and his family see Bilbao as the best 'springboard' for his future career.

It is claimed that the deal will be completed in the coming days, with Osuchukwu having turned down offers from Lille, Borussia Dortmund, Anderlecht and Copenhagen.

The move to Bilbao carries added significance for the goalkeeper, as he was previously part of the youth academy at Gazte Berriak, who are also based in northern Spain. He also spent time at Osasuna.