Even a huge downpour hasn't dampened their enthusiasm. It's extraordinary the difference a day makes here. There was barely a soul to see when I walked into Wimbledon early yesterday morning for the women's semi-finals. The concourses were relatively clear and the Centre Court was embarrassingly sparse for the mismatch between Venus Williams and Dinara Safina.

But early today, there were knots of fans shuffling along the main road, taxis pulling up and standing room only once again on the Underground trains.

Out on the field opposite Wimbledon's gates, there were the real obsessives, emerging from their tents into the cool morning air, bleary-eyed, slightly damp, but still desperate to secure one of the 6,000 general admission tickets that were going on sale. Within minutes of the gates opening they were already getting themselves entrenched on Henman Hill.

Correct that: if Murray wins through to Sunday - the first British man to play a Wimbledon final since Bunny Austin in 1938 - the Wimbledon authorities will be obliged to put up a sign officially naming that now world-famous sloping patch of grass "Murray's Mound". Bizarre, really, travelling all the way to Wimbledon to watch a giant telly, but there you are. At least, Wimbledon were up to speed yet again, placing a big screen in the new Court 2 for fans who want to watch in comfort.

And what of the great man? Well, he is staying in his apartment, which overlooks the Thames in south London, about a 20-minute drive from Wimbledon. Maggie the dog was quietly walked last night and everything is very much business as usual. In fact, Murray seems to be the coolest man at Wimbledon amid the frenzied crescendo.

His only worry is that roof, the one he castigated so thoroughly after his tough fourth-round encounter with the determined Stan Wawrinka. He has asked the authorities for at least 30 minutes' notice if he is playing under the Centre Court's £80 million lid. Looking at the clouds, there is every chance he will. Just as happened on Monday - and whatever the BBC claims in its constant denials - there will be massive pressure on Wimbledon to put Murray on late, even if the match does drift into the night. As far as the television people are concerned, the later the better, particularly after the spectacle we saw in Murray's dramatic match under the floodlights.

Wimbledon queue

Not much help to Jamie, Andy's brother, though. He is due to play his mixed doubles semi-final but discovered his partner, Liezel Huber, is first up on Court 1 in the women's doubles. But I will bet that the television companies would not mind Jamie following his brother on to Centre Court if there is even a remote chance.

Bums on seats

Crunch the crowd numbers and they are astonishing. There is extra capacity at Wimbledon this year offering around another 3,000 seats, but they still have to be filled - and in a recession. Yet every day has seen a record crowd and as of last night, the total attendance was at 420,115, well on course to beat last year's figures

How to label a phenomenon

Must be Murray Mania. Or Murray-mania. But what is this? A missive arrives from our man in the red pen department at The Times, who guides us daily through our grammatical worries. From today, it is officially Murraymania, although he gets a little carried away and suggests Andyoid for a "human tennis machine with a refreshingly bolshie attitude to conventional niceties, such as losing well". Might be able to find a place for that word come Sunday night.