The clock is already ticking towards Arne Slot and his players being reunited for pre-season next month.
There are two transfer windows this summer: one which opened on June 1 and June 10 — which was created so that teams participating in the Club World Cup could sign new players ahead of the tournament starting — and another, which opens on June 16 and closes on September 1.
The Reds have already secured the services of former Bayer Leverkusen wing-back Jeremie Frimpong, and there is optimism that his old teammate Wirtz will follow him to Anfield.
A fresh bid worth up to $153 million (£113 million) has been submitted, but a higher bid will be required to seal the deal.