Japanese sports outlet Nikkan Sports report that Liverpool have concrete interest in the defensive midfielder, with Brentford also said to be monitoring him.
Sano was born in Tsuyama, Okayama Prefecture, and came through the local football scene before turning professional with Machida Zelvia in Japan's second division — where he made 118 appearances over four seasons, developing the running and pressing habits that have become his trademark.
He moved to Kashima Antlers in J1 and made 48 appearances before Mainz signed him in July 2024 for approximately €2.5m.
His market value has since risen to €29.2m — a figure that will move significantly upward after his performance at the World Cup.
In the Bundesliga last season he started 34 games, contributing one goal and two assists. He was among the league's leaders for distance covered, pressing actions and duels won — a workhorse profile that suits any manager building a high-energy midfield.
His goal against Brazil — a composed right-footed strike from outside the area after he dispossessed Casemiro in midfield — was his first in senior international football.
Sano is contracted to Mainz until 2028 with no release clause, and the club hold complete control over any departure.
Mainz are expected to demand a fee of €50–60m if a sale were to materialise, which would make Sano the most expensive outgoing in the club's history — eclipsing the €31.5m Brighton paid for Brajan Gruda in 2024.
Sano's profile is one that tends to travel well — technically efficient rather than spectacular, disciplined without the ball, and capable of covering enormous ground over 90 minutes. Those qualities made him one of the Bundesliga's most reliable holding midfielders last season, and his World Cup moment against Brazil has now put him in front of a far wider audience.
Whether Liverpool or fellow Premier League suitors Brentford are willing to meet Mainz's valuation remains to be seen, but the price will only go in one direction from here.