Magnus Norman is the world’s best tennis coach. So the theory goes, in locker-rooms from Melbourne to Madrid. And after spending a revelatory half-hour on the practice court with him last week, I am not inclined to quibble.

Seven days ago in Paris, Norman was preparing his client Stan Wawrinka to face Rafael Nadal in a grand slam final. On Friday, he faced an even greater challenge: fixing my wonky backhand.

In his whispery Swedish mumble, Norman recommended earlier preparation, a looser grip and the same flick of the wrist you might use to deliver a Frisbee. After just a couple of attempts, I could hear a new and brighter note in the (formerly soggy) sound of ball on strings.

“Repetition is important for most of us,” said Norman, after cajoling me into another personal best: a first serve that flew down the ‘T’ at something greater than mobility-scooter pace.

“Wake Rafa up in the middle of the night and he can hit a forehand because he has done it so many times. It’s different with Roger [Federer]: he just has magic in his hands, so he practises in a less structured way. As a coach, you have to adapt to your player.”