At the age of 12, Barker was the British 12 and Under singles champion, but soon after the twins decided to focus on education and stayed away from tennis for four years.

[2] In their junior year the pair put together a streak of 35 consecutive wins, a run which ended in the semifinals of the NCAA Division I Championships.

At Wimbledon they entered the draw as wildcards and were eliminated in the first round by the tournament's top seeds, Jonas Björkman and Max Mirnyi.

Straight after his Wimbledon appearance, Barker won a Challenger title at Forest Hills, partnering American Huntley Montgomery, after which he attained his career best ranking of 161.

The lawsuit, which gained support from several high-profile doubles players including the Bryan brothers, was filed in a U.S. District Court in Houston during the 2005 US Open.