Private jet waits in vain as Mainz reject €30m Palace offer for Kaishu Sano | OneFootball

Mainz 05 have successfully resisted a late Premier League push for Japanese international Kaishu Sano, with the Bundesliga club refusing an offer exceeding €30m from Crystal Palace. The 25-year-old will remain with the Rheinhessen beyond the summer transfer deadline despite a dramatic final attempt to lure him to England.

Kicker reports that Conference League winners Palace submitted a base offer slightly above €30m while also proposing a significant sell-on percentage. The English club were apparently sufficiently confident of completing the transfer that a private jet was already waiting at Frankfurt Airport to take Sano to London.

Mainz never gave the move the necessary approval.

Get German Football News reported earlier on deadline day that an unnamed Premier League club had submitted an offer in the €30m range, placing sporting CEO Christian Heidel and sporting director Niko Bungert in the uncomfortable position of weighing an enormous return against the sporting consequences of losing their most important midfielder without sufficient time to replace him.

Crystal Palace have now been revealed as the interested club.

Mainz refuse to compromise on Sano valuation

Mainz’s rejection reflects a stance the club maintained throughout the summer. Kicker reports that the Rheinhessen were unwilling to negotiate significantly below a figure of approximately €60m. Sano remains under contract through 2028 and possesses no release clause, leaving Mainz with complete control over his immediate future.

That negotiating position had already become apparent earlier in the window.

When RB Leipzig emerged among a growing list of potential suitors, GGFN detailed Mainz’s determination to retain Sano unless presented with an extraordinary offer. Heidel had previously described the Japanese international as the “heart of our game” and insisted that €25m would not come close to an acceptable valuation.

Interest naturally increased following another strong campaign and Sano’s performances for Japan at the 2026 World Cup.

Nevertheless, Mainz ultimately refused an immediate profit of nearly €30m on a player who cost approximately €2.5m when signed from Kashima Antlers in summer 2024. The decision constitutes a significant statement from a club traditionally accustomed to developing players before selling them for substantial profits.

Brajan Gruda’s move to Brighton two summers ago established a new Mainz record at approximately €35m. Palace’s proposed Sano package – through the proposed sell-on percentage – might have eventually exceeded that figure.

Mainz instead decided that Sano’s sporting value was worth more.

Sano remains the heart of Mainz midfield

Few Bundesliga transfers have produced returns comparable to Mainz’s modest investment in Sano. The Japanese midfielder immediately established himself alongside Nadiem Amiri after arriving in Germany. His durability quickly became extraordinary.

Sano started all 34 Bundesliga fixtures during his first season and played the full 90 minutes in all but two. By September 2025, he had completed 3,884 of a possible 3,900 competitive minutes since joining the club.

Get German Football News highlighted his remarkable “Iron Man” status after Sano scored his first Bundesliga goal and supplied two assists against Augsburg. His influence subsequently expanded beyond defensive work. Sano developed into Mainz’s primary ball-winner and one of the most important links between the defensive and attacking phases. His capacity to regain possession, escape pressure and accelerate forward enabled the entire team to operate more aggressively around him.

As detailed in Get German Football News’s 2026/27 Mainz tactical preview, the club assembled an unusually deep squad over the summer but remained significantly more difficult to project without Sano anchoring midfield.

Mainz recruited Eric Martel and retained Sota Kawasaki as players capable of working in deeper midfield roles. Neither represents a simple like-for-like replacement. The prediction that Mainz could again challenge toward the upper reaches of the Bundesliga consequently came with one major qualification: Sano needed to stay.

He has.

Hong Hyun-seok closing in on Midtjylland move

One Mainz midfielder may still depart despite the closure of the German transfer window. Sky Germany reports that South Korean international Hong Hyun-seok is close to joining Danish side FC Midtjylland on loan with a purchase option.

The Danish transfer window remains open until September 2, allowing Mainz additional time to complete the transaction. Hong is expected to undergo his medical on Wednesday. A proposed move to Hertha BSC collapsed on Monday, but Midtjylland have subsequently reached an agreement with Mainz.

The 27-year-old has struggled to establish himself since arriving from KAA Gent for approximately €4m in summer 2024.

Get German Football News covered Mainz’s efforts to revive Hong’s career with another loan move earlier this year. After an unsuccessful spell at Nantes, Hong spent the second half of last season at KAA Gent.

The prospective Midtjylland agreement would now give Mainz another opportunity to move the midfielder permanently at the conclusion of the loan.