Hojlund's loan move from Man United included a £38m obligation to buy if Napoli secured Champions League football, and his 11th Serie A goal of the campaign helped them achieve that.
The 23-year-old has found a new lease of life since leaving Old Trafford after struggling in England, with both sides delighted that a transfer has been agreed.
Speaking after his move was officially confirmed, Hojlund said it was "weird" saying goodbye to Man United because he already felt like he was a Napoli player, arguably aiming a subtle dig at the Premier League side.
“I’m now officially a Napoli player and I’m saying goodbye to Manchester United," the Danish striker wrote.
“That feels weird, because for the past year I already feel like a Napoli player. The way you fans supported me, made me feel like home and let me find my confidence again is something I’m so grateful for.
“To say goodbye to Manchester United is something that kinda feels emotional too. My childhood dream came true by playing at Old Trafford in a red jersey.
“So the goal today symbolizes a new confident start, in which I will give everything for the time ahead to Napoli, and a thank you to all the fans, players and staff of Manchester United who made the dream I had as a kid come true. It’s time for new dreams, so let’s chase them”.
Hojlund could come up against the Red Devils in the Champions League next season if they get drawn against each other in the league phase.