Roger Federer and Andy Murray play an unusual match floating on a raft, as the World No 1 prepares for his comeback

The pair had a knock up floating down the river Limmat ahead of their exhibition match in Zurich

Roger Federer and Andy Murray both took an usual approach to preparing for a charity exhibition match against one another – by having a knock-up on a raft in the middle of the river Limmat.

Murray will return to a tennis court for the first time in over four weeks when he takes on Federer in Monday night’s ‘Match for Africa’, which will be staged at Zurich’s Hallenstadion.

And to promote the match, which will raise money for the Roger Federer Foundation, the pair had a casual match on a floating raft tethered in the middle of the Limmat, a large river which runs through the southern part of the city of Zurich.

The duo will raise money for the Roger Federer Foundation (Getty)

Murray travelled to the city by private jet on Monday morning after pulling out of Great Britain’s Davis Cup tie against France because of an elbow injury.

In his absence, Great Britain suffered their first Davis Cup whitewash since 2009, with Kyle Edmund and Dan Evans losing their rubbers on the first day of competition before veteran pair Nicolas Mahut and Julien Benneteau beat Jamie Murray and Dom Inglot in the doubles.

Murray is expected to return to competitive action at the Monte Carlo Masters, which begins this weekend, having lost to Vasek Pospisil in the first round at Indian Wells and withdrawing from the Miami Open.

And the World No 1, who has been training in Nice at the Patrick Mouratgolou Academy, has been relatively happy with the speed of his recovery ahead of the clay court swing.

Murray hopes to return at the Monte Carlo Masters (Getty)

“I'm doing better, I've been practising here for the last four or five days,” Murray said ahead of his return.

“I had the problem with my elbow but the good thing was I could do everything except serve. So the last four or five days I have started to serve a little bit.

“I'm not serving as fast as I would like yet but am hoping over the next five or six days I will be able to start serving like normal again.”