Sadio Mane’s move to Bayern Munich last summer appeared to be the perfect next step in an already impressive career.

The Senegal forward had helped Liverpool to Champions League and Premier League glory but was ready for a fresh challenge.

Alas, all that has proved too good to be true. Mane’s time in Bavaria so far has been a disaster and a whole load of pent-up frustration erupted into the open this week.

An on-pitch argument between Sadio Mane (left) and Leroy Sane (right) escalated into a dressing room bust-up with the latter suffering a bloodied lip

Sane (right) appeared to hide his lower lip as the Bayern Munich players returned home

Mane (front row, second from right) and Leroy Sane (back right) were both pictured in Bayern training just hours after their meeting with club chiefs

The two players trained alongside one another throughout the session but Mane has been dropped for the upcoming game against Hoffenheim and also fined

The usually mild-mannered Mane took a swing at Leroy Sane in the Bayern dressing room after Tuesday night’s Champions League capitulation against Manchester City.

The slap bust open Sane’s lower lip, leaving him bloodied and the pair had to be separated by team-mates.

It is a remarkable conclusion to a row which had started on the pitch when Sane demanded Mane come deep and collect the ball a little more.

But it also spoke of broader irritations for Mane since he swapped Merseyside for Munich – about his form, his role in the team and injury struggles which some fear has curbed his talent.

Worse, there are suggestions the injury has robbed him of some trademark pace and left Mane less committed in one-on-one duels.

Moving from the empathetic Klopp to the more matter-of-fact Nagelsmann proved a difficult adaption with Mane having to start from scratch having been comfortable in his role at Anfield.