Serena Williams to return to competitive tennis at Eastbourne tournament . The world number one will play in the first round of Wimbledon for a second time since her knee injury last year. Serena 's sister Venus also returns to action in same tournament . They will take their place in a top-class line-up which has 13 of the top 20 players in the WTA world rankings , including new French Open champion Li Na of China . Roger Federer pulls out of grass court tournament in Halle .
Serena Williams to return to competitive tennis at Eastbourne tournament . The world number one will play in the first round of Wimbledon for a second time since her knee injury last year. Serena 's sister Venus also returns to action in same tournament . Roger Federer pulls out of grass court tournament in Halle .