London: Defending champion Roger Federer and Andy Murray take centre stage at Wimbledon on Wednesday while Maria Sharapova has to settle for a spot away from the two major show courts.
Federer, bidding to become the first man to win the title eight times, tackles Ukraine's Sergiy Stakhovsky on Centre Court.
Murray, the US Open and Olympic champion, switches to Court One to play Lu Yen-Hsun, the Taiwan player who beat him at the 2008 Olympics.
But Sharapova, the third seed and 2004 champion, takes on Portuguese qualifier Michelle Larcher de Brito out on Court Two.
That will raise eyebrows with the low-key clash between Fernando Verdasco and Julien Benneteau, and the match-up featuring Petra Kivtova, the 2011 women's champion, against Yaroslava Shvedova taking place on Court One.
Murray, beaten by Federer in last year's final, is well aware of the threat posed by Lu, who also beat Andy Roddick at Wimbledon in 2010.
"I know quite a lot about him. I lost to him in the Olympics in 2008 in Beijing. It was a very tough loss for me. I learnt a lot from that match," Murray said.
"He's made the quarters here before. He's beaten Roddick here and plays well on grass. So I'll need to be ready."
If Murray sees off Lu it will be the 108th Grand Slam match win of his career, taking him further clear of Fred Perry's record for a British player at a major.
Also in action on Wednesday are second seeded Victoria Azarenka against experienced Italian Flavia Pennetta.
Lleyton Hewitt, the 2002 champion who put out Swiss 11th seed Stanislas Wawrinka in the first round, takes on German qualifier Dustin Brown.
Order of play
Centre Court (1200GMT)
Flavia Pennetta (ITA) v Victoria Azarenka (BLR x2)
Jo-Wilfried Tsonga (FRA x6) v Ernests Gulbis (LAT)
Sergiy Stakhovsky (UKR) v Roger Federer (SUI x3)
Court One (1200GMT)
Fernando Verdasco (ESP) v Julien Benneteau (FRA x31)
Lu Yen-Hsun (TPE) v Andy Murray (GBR x2)
Petra Kvitova (CZE x8) v Yaroslava Shvedova (KAZ)
Court Two (1030GMT)
Dustin Brown (GER) v Lleyton Hewitt (AUS)
Petra Cetkovska (CZE) v Caroline Wozniacki (DEN x9)
Michelle Larcher De Brito (POR) v Maria Sharapova (RUS x3)
Kenny De Schepper (FRA) v Marin Cilic (CRO x10)
Court Three (1030GMT)
John Isner (USA x18) v Adrian Mannarino (FRA)
Nicolas Almagro (ESP x15) v Guillaume Rufin (FRA)
Sloane Stephens (USA x17) v Andrea Petkovic (GER)
Marion Bartoli (FRA x15) v Christina McHale (USA)
Court 12 (1030GMT)
Radek Stepanek (CZE) v Jerzy Janowicz (POL x24)
Eugenie Bouchard (CAN) v Ana Ivanovic (SRB x12)
Tommy Robredo (ESP x32) v Nicolas Mahut (FRA)
Court 18 (1030GMT)
Alize Cornet (FRA x29) v Hsieh Su-Wei (TPE)
Vasek Pospisil (CAN) v Mikhail Youzhny (RUS x20)
Juan Monaco (ARG x22) v Rajeev Ram (USA)
Camila Giorgi (ITA) v Sorana Cirstea (ROM x22)