Nick Bollettieri: Poker-faced Murray holds all the aces against lefty Lopez

Take a look at Andy Murray when he walks on to Centre Court this afternoon. There is a man in control of his self, a man with the demeanour of a winner. It is tremendous to see.

He is a strong favourite to beat Feliciano Lopez and so take his place in the semi-finals for the third year in a row. There is a difference this year, though, and that guy out there looks like a new Andy Murray. I tell you he has impressed me like never before over the last nine days – sure on the court, but off it too. The way he has talked with the press and faced up in interviews, a young man at ease, confident but not arrogant, not getting drawn into saying anything rash or bigging himself up or getting involved in any silly business.

I see Murray as being twofold better than last year – when he was outplayed by a rampant Rafael Nadal in the last four. There is a huge, huge difference and I'm feeling very, very positive about our boy. His game has improved in key areas – the serve is bigger and more consistent for a start, but above all it looks to me as if it's down to confidence.

There was a moment against Richard Gasquet on Monday – and that was a damn fine all-round performance by Murray – when he was 30 love down on his serve. Pow. Pow. Two aces and it was 30-all and he was back on track. At a key point in a game, in the match in fact, he was prepared to – and able to – go big.

There was less emotion on show as well from Murray. He's beginning to resemble a poker player at the table for a big game in Vegas. He is not giving anything away to his opponent. The concentration is there to add to the passion that has always been hot and strong inside Andy Murray.

Now Lopez's main weapon is his serve. And what's the most striking part of Murray's game? His return of serve. He has one of the best in the game. Advantage Murray, guys. Even though Lopez is a lefty I don't expect him to cause Murray too many problems. He certainly hasn't when they have met in the past – in four matches, Lopez has taken only one set. They played each other twice last year, both on hard courts in Valencia and LA, but this will be their first meeting on grass.

Lopez has had to battle goddam hard to get to this stage – which equals his best performance at Wimbledon (he's lost in the quarters twice, against Marat Safin in 2008 and Lleyton Hewitt back in 2005). Against Lukasz Kubot, the young Polish outsider, in the last round, it went to five sets but, hey he got through and that's all that matters now.

If I was setting up Lopez for this match I would urge him to think of a different strategy. In a straight match-up, if you break them down, number by number, Murray has the aces so Lopez has to mix it up. He's got to get forward, surprise Murray, mix up that serve and send down some high kickers. But holy cow, is he going to have to play some to challenge the guy facing him across the net.

Round by round Murray has been hotting up. His game is developing and he is becoming more offensive – you cannot, I repeat, cannot win a Grand Slam by staying back and taking the defensive option. Safety first is not enough. Murray has it, or should I say the new Murray, the one with the demeanour, the guy who is walking tall and looking like he can keep on growing. I like what I see – who wouldn't? – and that is why he is the big favourite today.

Today's big match

Andy Murray v Feliciano Lopez:

How they match up

British Nationality Spanish

24 Age 29

London Residence Madrid

Right-handed Plays Left-handed

6ft 3in Height 6ft 2in

4 World ranking 44

17 Career titles 2

$16m Career prize-money $5.8m

W27 L5 Wimbledon record W24 L9

Semi-final (2) Wimbledon best Quarters (3)

W4 L0 Head-to-head W0 L4

1-10 Odds 5-1

Bollettieri's prediction Murray in four

Coaching Report: Big-hitting German matches favourite for aggression

Sabine Lisicki

Holy mackerel, the first two quarter-finals in the women's singles could not have offered a greater contrast. Sabine Lisicki against Marion Bartoli saw every point fought over between a pair of great scrappers – the other was all one way. Oh boy, did Maria Sharapova batter Dominika Cibulkova. The poor Slovak could do nothing to stop the onslaught.

But let's deal with Lisicki's win first; they let her in as a wild card, now she's a semi-finalist. As her run has gone on through the Championships – and she certainly would not have expected to wake up this morning and begin planning for a semi-final – so her confidence has grown and her play expanded.

It was noticeable against Li Na – that was the win that set her up – she began to use the drop shot and it was even more in evidence yesterday as she tried to work Bartoli around. Bang, bang would go the big forehand and then with Bartoli, who is a real bundle of energy, man what a fighter, on the back foot – ping, the drop shot and point won.

The only time I was worried about Sabine was when she missed a succession of match points. All of a sudden Bartoli was buzzing again, that girl fights and fights. That could have thrown Lisicki but she showed growing maturity – remember she is still only 21 but as tough as nails – and finished the job.

Lisicki has always been a big hitter. She loves to crash down those forehands and power was important yesterday. She served nine aces to Bartoli's one and had a fastest serve of 121 mph. Her serving average was over 100mph and that is pretty damn good going. The German is an aggressive player, which brings me on to Sharapova.

Maria Sharapova

It took an hour of my day to watch Sharapova win. Boy, oh boy, did she steamroller her opponent. When Maria gets on a roll she takes some stopping. All that aggression, Cibulkova could do nothing – two games in two sets, that's power play, I'm telling you.

It has been a while since Sharapova had a really good Wimbledon – 2006 was her last appearance in a semi-final. Sure, some of that was down to her injury problems and they took a deal of getting over. It's good to see her back at her best at these Championships.

Tomorrow I'll be taking a closer look at their match-up in the semi-final, but I'm out there on Twitter too if you want any more in the meantime.

Mr B's A-Zee

Q is for the queen of Wimbledon, Martina Navratilova. Over three decades she won nine singles titles on the grass. Add in seven doubles and four mixed doubles crowns and you can see why she reigns supreme here.

R could be for rain but I like to be positive so let's say roof. It has already come in pretty useful – there wouldn't have been too much to keep us busy yesterday if it hadn't been for the roof over Centre Court. I actually think Andy Murray is suited to having it shut.

Win a week at my academy

Want a week's tennis holiday at my IMG Nick Bollettieri Academy in Florida? Included in the prize is five days' top-class tuition. The prize can be for an adult wanting to shape up his or her game, or for a child who wants to follow in the footsteps of the likes of Andre Agassi, Monica Seles and Maria Sharapova, among other players who went from being kids under my tuition to No 1 in the world.

What you have to do is answer this question: How many games will there be in total in Andy Murray's match today? Email your answer (and predict how long the match will last, in case we need a tie-break) to me at bolly@independent.co.uk and the correct one will win a signed hat or T-shirt.

I'll be putting a question every day and all the winners will go into the hat for the big prize to be drawn at the end of the fortnight: a week at the IMG Nick Bollettieri Academy.

Coaching tip of the day

Volleying can be a game-changing skill but don't limit your practising of the shot to standing at the net while your partner hits balls at you. How many times in a match do you hit a volley while standing still? You need to practise on the move – that's the only way you will learn to transfer the skill properly to a match.