Vušković, who joined Spurs from Hajduk Split in summer 2023 for around €11m on a contract until 2030, made 30 appearances for Hamburg this season and broke the Bundesliga record for aerial duels won in a single match — 18 against Union Berlin.
The Independent reported that Spurs plan to offer him a new long-term contract before sending him back to Hamburg for a further loan season, though Vušković himself has suggested he wants to be involved with the first team.
Alderweireld, who spent six years at Tottenham before leaving in 2021, faced Vušković in Belgian football and was immediately struck by his profile.
"I played against Luka Vuskovic in Belgium when he played for Westerlo. I think he's physically very strong for his age, so that's a positive. He will only get stronger and stronger. If you're in the team of the year playing for Hamburg, it means you're doing well."
He spoke about what makes Vušković's profile so distinctive.
"He's more than just a defender. He scores all of the goals, and he's good with passing as well. He's not a typical defender — not only a no-nonsense defender. He has a lot more qualities about him," he told the London Evening Standard.
The Vertonghen comparison was his highest endorsement.
"He's strong, quick, good with his feet, even in the attacking box of the opponent he can win some headers, score some goals — he's a very all-round complete defender. He will get the opportunity, and he has everything to become an unbelievable centre-back."
Vušković wants to remain at Hamburg next season to play alongside his brother Mario once the latter's doping ban expires in November. The contract decision, however, will wait until after the World Cup, where he represents Croatia.