Wimbledon Day Four

The benchmark was set for all men's tennis players to reach last night, as the world number one Novak Djokovic was in imperious form beating Ryan Harrison in three fantastic sets.

Harrison played very close to his maximum in the match of the tournament so far last night, under the centre court roof.

Someone who will look to match Djokovic is the home hope, Andy Murray. The world number four demolished Nikolay Davydenko and now faces quite literally a much bigger test in 6 ft 10 Ivo Karlovic.

(Andy Murray faces a tall task against Ivo Karlovic today in his second round match picture: Radio Times)

The giant, famous for his serve, which when firing is unplayable, possesses little quality apart from this huge weapon but if that aspect of his game is firing, it will take great concentration from one of the game's best returners to advance through to the third round.

Also in action on centre court is Rafael Nadal who should face little opposition against Czech Republic's Lukas Rosol.

(Milos Raonic faces first real challenge of his Wimbledon credentials against, former Queens champion, Sam Querrey Picture: Canadian Press).

A match almost certain to see a couple of tie-breaks is Sam Querrey versus Milos Raonic. Two tall powerful men who serve big, Raonic is seen by many tennis experts as a future world number one and could potentially upset Murray in the fourth round this year. Querrey however reminded everyone how effective he was on grass reaching the Queens semi-finals and if he is at his best could upset the young upstart.

Britain's James Ward is in second round action against Mardy Fish. The British number three hasn't quite progressed since his Queens semi-final last year and faces a tough task against the world number 12. An irregular heartbeat forced the American out of this year's French Open and question marks over the 30 year old's health might open the door for an upset.

(James Ward faces tough task today against Mardy Fish Picture: Getty Images)

David Ferrer and Andy Roddick both look to continue their progress. The two popular players are returning to SW19 for the third straight day as weather has begun to play havoc with the Wimbledon schedule. The tournament directors are under severe pressure to get all second round matches wrapped up today. Ferrer and Roddick  take on Kenny De Schepper and Bjorn Phau respectively.

Gilles Simon has caused quite a stir this week with his criticism of equal pay in men's and women's tennis. The Frenchman will be keen to highlight his talents as he takes on grasscourt specialist Xavier Malisse. His countryman Jo Wilfred Tsonga was immense against Lleyton Hewitt and may be most likely to upset the top four in the men's game. Guillermo Garcia-Lopez is his second round opponent.

Two crowd favourites meet in a match which could beat them all for entertainment today. Grigor Dimitrov plays Marcus Baghdatis with the winner taking on the victor in the Karlovic Murray contest. Dimitrov won over the crowd and nearly the title at the Aegon Championships two weeks ago and his warm personality and incredible shot variety is likely to continue to win supporters in England. His opponent, Baghdatis had the crowd in the palm of his hands throughout his memorable third round clash with Djokovic last year and will be keen to stunt the 21 year old's progress.

Women's world number one, Maria Sharapova, is returning to complete her second round clash with Tsveta Pironkova after an almighty scare at the close of play yesterday. The Bulgarian squandered  four set points before relinquishing control to the number one seed who at 7-6 and 3-1 up in the second set is closing in on victory.

(Maria Sharapova was rattled yesterday but survived scare to take a set and break lead picture: Anja Niedringhas)

Reigning champion Petra Kvitova overcame nerves to come through in straight sets in her first match 6-4 6-4 and now faces one of the five Brits still in the singles competition at this year's Wimbledon. Elena Baltacha faces a huge challenge against the world number four and may need the powerful Czech to be completely overcome with nerves to stand any chance of progressing further. Anne Keothavong also faces a tough task against last month's French Open finalist, Sara Errani. Whilst Ana Ivanovic, Serena Williams and Victoria Azarenka are also scheduled for second round competition today.