Tennis on grass is all about footwork but the semi-final between Jannik Sinner and Novak Djokovic will be all about footwear.

It matters not whether a contender has the biggest serve, the fiercest forehand or heaviest backhand: if he can’t sort his feet out to get into position, he is doomed.

Both Djokovic and Sinner were reminded of this sometimes painful fact in recent rounds.

Sinner slipped and jarred his right elbow as he fell in his fourth round match with Grigor Dimitrov. That led to an anxious 48 hours as he and his team waited to see whether the joint would recover in time to face Ben Shelton (both he and it did).

Djokovic slipped and did the splits on match point against Flavio Cobolli. Everyone on Centre Court held their breath as the seven-time champion clutched his hip and grimaced.

He got up and closed out the win but headed home for treatment, recovery and a lot of finger crossing in the hope that there would be no lingering after effects.

Since his fall, Sinner has come up with a plan to remain upright for the remainder of his time at The Championships.

“I play with completely new shoes to have more grip,” he said. “I haven't even played practice [in them]. It was completely new, which usually on other surfaces I don’t do.

“On grass, the main priority is to have lots of grip. So, yeah, I have to get used to it.”

Djokovic, at 38 and now playing a record 14th Wimbledon semi-final, is a little more experienced in these matters but he, too, has tinkered with his shoes over the years to get the maximum traction possible on the grass.

“It was a nasty fall,” Djokovic said. “It was very awkward. That happens on the grass. I've had quite a few of those throughout my grass court career.

“Obviously, the body is not the same today like it was before, so I guess the real impact or effect of what happened I will feel tomorrow. So let’s see.

“I’m hoping the next 24, 48 hours that the severity of what was happening on the court and what happened is not too bad, that I’ll be able to play at my best and free of pain in two days.”

And he knows that he needs to be at his very best to beat the world No.1.

They last met in the Roland-Garros semi-finals and Djokovic did not win a set. He trails their head-to-head record 4-5 with Sinner winning the last four matches.

But on grass, he has a 2-0 winning record against the Italian, winning their 2022 quarter-final here and their semi-final the following year. But that was before Sinner developed into a Grand Slam winner (he has won one US and two Australian Opens) and the best player in the world.

“Back in the days, a couple of years ago, [since then] many things have changed for me,” Sinner said.

“I feel that before matches I’m more comfortable, let’s say, or confident. I believe that I’m a different player, different person. Hopefully I can say that I’m more mature, too.”

Maturity is a word Djokovic is getting a little tired of.

At 38, he knows that “mature” in his case means old. Sinner is 15 years his junior and plays a game very similar to his own (precision striking from the back of the court and a near-impregnable serve).

What Djokovic is trying to achieve is unheralded – to win a 25th Grand Slam title – and doing it against men who are half his age appears almost impossible.

“Sinner and Alcaraz, we know they’re the dominant force right now in the tennis,” he said after beating Cobolli. “If I want to at least go a step further, I have to beat the No.1 in the world and eventually play Alcaraz in the final.

“Physically I hope that I’ll be able to sustain that. That’s more of a concern than game-wise. I think game-wise the way I’m feeling the ball when I’m fit and ready, I feel like I can go toe-to-toe with those guys and even beat them if I’m playing my best.”

If he is fully fit, Djokovic still believes he has his chance on his beloved Centre Court. If Sinner’s elbow is feeling better, he believes he is ready to reach his first final.

It will all come down to new shoes and perfect footwork.

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