Wimbledon 2015: Nick Bollettieri - To beat Serena Williams in the battle of the grunters Maria Sharapova needs to hit homers from the off

If you have a ticket for Centre Court, bring your earplugs, it is the battle of the grunters. As usual, some people are making a fuss about the noise Maria Sharapova makes when playing. Well, Serena Williams does it as well, and so do plenty of the other players, male and female. Is it a problem for players? That’s up to the umpires, not me. They are in charge.

There’s also been comment about the fact that Serena has beaten Maria 16 times on the bounce. If I was advising Maria I’d be telling her no one wins all the time. I might even tell her about the time Vitas Gerulaitis beat Jimmy Connors at Madison Square Garden after 16 successive defeats. Asked how he did it Vitas famously said: “Because nobody beats Vitas Gerulaitis 17 times in a row.”

Maria needs to summon up some of that spirit. She needs to tell herself, ‘I’ve lost so many times playing this way I’ve nothing to lose here. I should go for it.’ Maria doesn’t want to get into long seven, eight, nine 10-shot rallies. Her best chance is to go big all the time, to look for those home-runs. If she simply aims to get the ball back it will not be enough, even if she is changing the pace. She has to play her natural game, and her natural game is to be very aggressive. I am sure her coach, Sven Groeneveld, will be telling her any defensive shots will be pounced on so she should be positive.

Maybe she should throw in some junk shots, some high lobs and the likes, because if it ends up as a hitting game Serena will win. People are always talking about offense, about shots like Maria’s forehand, but defence is just as important and Serena’s defence is better. She runs down balls others do not reach.

The other big factor will be the serve. Maria needs to get her first serve in, and if she doesn’t, she has to be bold with her second. The strategy of Serena is to go for big returns against any defensive second serve, so Maria cannot give her that chance.

Serena’s other great advantage is she has two things to rely on when the game gets tough, a big serve and a big return. She’ll be tough to beat, but Heather Watson came close and it is not impossible.

Besides, there are the intangibles. Nobody knows how players will be as a match develops. Are they feeling great? Did something happen last night? Is their focus distracted? Sport is unpredictable, that is why we watch it.

Both girls were tested in their quarter-finals, but both had the ability and mental strength to come through it. They are both champions and it should be a great match. I do not, though, agree with people who say this is effectively the final, that whoever wins will be lifting the Venus Rosewater Dish on Saturday. I would never say that. You never know what will happen. Let’s see who’s in the final first before we start predicting a winner.

Garbine Muguruza is the unknown in the semi-finals. No one would have expected her to make the last four but she is a hard-hitting girl, very attacking and very dangerous. It will be an intriguing match because it is never easy against Agnieszka Radwanska; she has very good groundies and she is not going to give you the match, you have to beat her.

The firepower of Muguruza could decide it, but Radwanska is one of those players who makes an opponent over-hit. She doesn’t miss herself, and she gets everything back with very good depth.

Eventually you get pissed off and say: “To hell with it, I am going to go for a big one.” Before you know it you’ve gone long, or wide, and lost the point. That’s Radwanska’s game, she forces you to overhit. It is firepower against steadiness with Radwanska’s experience giving her a slight edge.

To find out Bollettieri's top tip on day nine of Wimbledon 2015, watch the video below:

The Murrays are going for a family double with Andy’s brother Jamie in the semi-finals of the men’s doubles. I was asked when a coach makes the decision to suggest his player focuses on doubles.

The bottom line is a player normally switches because he realises he’s gone as far as he can in singles, and he is either not high enough in the rankings to make a living, or he is not doing well enough to satisfy his ambitions. If he is a good doubles player, why not concentrate on that?

Max Mirnyi, who I coached, is a good example of the latter. He reached 18th in the world in singles, which is pretty darn good, but he had only made one Grand Slam quarter-final and he just felt that was it. He had the right game for doubles – a big serve and good, aggressive net play – and had already won titles so he began concentrating on that. In men’s and mixed doubles he’s won 10 Grand Slam titles, Olympic gold and the bulk of his $10m career prize money, so it was a very good decision.

The big difference between the two is in doubles a weakness in a player’s game can be protected by having a partner who is strong in that area. So if you have an ordinary serve, pick a partner with a strong one. If they are not great on the return, and you are, you have the makings of a good partnership.

In singles you can’t protect a weakness. You are on your own. You have to cover the whole court yourself. In doubles you are in a team. Singles is a lonely game. There is no one to tap you on the backside and gee you up when you make a mistake.

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