Barcelona chose not to exercise their option to sign him permanently for £26 million.
A year ago Rashford's United career looked finished — sidelined after a public breakdown with then-manager Ruben Amorim and shipped out to Aston Villa for the second half of the season — before Barcelona offered an unlikely reset. He delivered on it: 14 goals in 49 appearances, a goal in an El Clásico win, and a starring role as Barcelona retained their La Liga title, even if a regular starting spot never materialised with Lamine Yamal and Raphinha established on the flanks.
"I'm very grateful to everyone at the club for making my time here such a positive and memorable experience. I've enjoyed every moment and will take many special memories with me. I wish the club and all its supporters the very best of luck and every success in the season ahead. Visca el Barca," Rashford wrote.
Team-mates were quick to respond. Marc Bernal wrote underneath the post: "I wish you all the best, my brother. It has been a pleasure to share the dressing room with a player like you," while Raphinha and Gavi were among others who left messages of their own.
Barcelona's decision not to trigger the buy clause hardened once the club moved for alternative attacking options this summer, spending £70 million to sign Anthony Gordon from Newcastle and adding Karim Adeyemi from Borussia Dortmund, signings that made a repeat pursuit of Rashford — even at a reduced price, as Barcelona are said to have explored — largely academic.
Rashford is now back at Manchester United, where his long-term future remains unresolved, with manager Michael Carrick yet to indicate whether the forward features in his plans for the season starting August 22 against newly promoted Hull City.
A boyhood United fan who came through the club's academy, Rashford has scored 138 goals in 426 appearances for the club since his 2016 debut, though his final season and a half in Manchester were turbulent, punctuated by the Villa loan and his eventual Barcelona move.
He added a further goal for England at this summer's World Cup, where the team reached the semi-finals under Thomas Tuchel, but questions over his best position and consistency have followed him throughout a career that has never quite settled since his breakthrough a decade ago.