Liverpool would have to pay a compensation package to Sporting CP to secure the services of manager Ruben Amorim, the UK Telegraph reports.
Amorim is looking like Jurgen Klopp’s successor ahead of next season.
And if the Reds decide he is the man to lead the team forward, they would have to activate a release clause in his contract.
Amorim can be allowed to leave Sporting for as little as €15 million (£13m/$16m) when a release clause becomes active in the summer.
That fee drops to €10m (£8.5m/$10.5m) the following season.
Xabi Alonso, who was deemed a big favourite for the Liverpool job, on Friday announced his decision to stay with Bayer Leverkusen.