Serena Williams of the United States returns a shot to Barbora Zahlavova Strycova of the Czech Republic during a first round women's singles match at the All England Lawn Tennis Championships at Wimbledon, England, June 26, 2012. (AP)

Serena Williams of the United States returns a shot against Barbora Zahlavova Strycova of the Czech Republic during a first round women's singles match at the All England Lawn Tennis Championships at Wimbledon. (AP)

Serena Williams of the United States returns a shot to Barbora Zahlavova Strycova of the Czech Republic. (AP)

Serena Williams of the United States reacts during a first round women's singles match against Barbora Zahlavova Strycova at Wimbledon. (AP)

Another shot of Serena Williams of the United States reacting during a first round women's singles match against Barbora Zahlavova Strycova at Wimbledon. (AP)

Serena Williams of the United State during her straight-sets victory over Barbora Zahlavova Strycova at Wimbledon. (AP)