Rafael Nadal (ESP)  v Martin Klizan (SVK) – 2nd on Centre Court
Ordinarily you’d bet good money on Nadal breezing through this clash unscathed. World number 51 Martin Klizan was knocked out in the first round last year and failed to make it past the second in 2012. But Nadal has suffered an identical run of poor grass court form. His three-match losing streak saw him knocked out of Wimbledon by Lukas Rosol in dramatic fashion in 2012 before Belgian Steve Darcis pulled off a major upset, beating the 2011 champion in straight sets last year. Add a defeat at the hands of American Dustin Brown at the Halle Open earlier this month and Nadal comes into this first round clash with question marks next to his name. It should be in his power to overcome his big-hitting Slovakian opponent, but stranger things have happened…
Maria Sharapova (RUS)  V Samantha Murray (GBR) – 3rd on No.1 Court
Samantha Murray may share her nationality and a surname with British number one Andy Murray but that’s where the similarities end. The 26-year-old is ranked 242 in the world and has never won a set in a Grand Slam. In contrast, Sharapova comes into Wimbledon fresh from her victory at Roland Garros – her fifth Slam – but a second Wimbledon title still eludes her. The 2004 champion has only made one final since, suffering a shock second round loss in 2013 to fellow screecher Michelle Larcher de Brito. This year she’s a woman on a mission – and Murray is unlikely to be the stumbling block.
Heather Watson (GBR) v Ajla Tomljanovic (CRO) – 2nd on No.3 Court
With Laura Robson still out of action following wrist surgery, world number 60 Watson is the nation’s best hope of having a British woman still competing in the second week. The British number one’s opponent is ranked just seven places above her and, following Watson’s run to the semi-finals at last week’s Aegon International in Eastbourne, is certainly in her reach. But the home favourite will have to tread carefully. Her 21-year-old Croatian opponent caused carnage at the French Open last month, seeing off 2010 champion Francesca Schiavone, Elena Vesnina and Agnieszka Radwanska in the first three rounds. She’s certainly capable of rising to the occasion.
Roger Federer (SUI)  v Paolo Lorenzi (ITA) – 2nd on No.1 Court
For former world number one Roger Federer, Wimbledon is a home away from home. He’s lifted the trophy a record seven times in eight finals, although last year’s shock second round defeat to Sergiy Stakhovsky is something he’ll be hoping to brush under the carpet this afternoon. Despite an early loss at the French Open, he comes to SW19 in good form, having recaptured the Halle grass court title (his seventh) earlier this month. Clay court specialist Lorenzi shouldn’t cause him too much bother. Ranked 83rd in the world, the 32-year-old Italian has lost his only two matches on grass this season – at Queen’s and then the Topshelf Open – and should cause Federer few problems in their first ever meeting.
Serena Williams (USA)  v Anna Tatishvili (USA) – 3rd on Centre Court
Serena Williams has got her hands on the All England Club trophy five times, her last victory coming in 2012 after a three-set battle against Agnieszka Radwanska. Today the 32-year-old steps out onto Centre Court as world number one, continuing to see off younger challengers, although falling in the second round of the French Open to Garbine Muruguza of Spain. At Wimbledon she remains a strong favourite to avenge her shock fourth round defeat to Sabine Lisicki in 2013. World number 114 Anna Tatishvilli had better watch out.
Coverage of Wimbledon begins at 11:30am on BBC2 and 1:45pm on BBC1