Serena Williams has withdrawn from the Swedish Open in Bastad with an elbow injury.

The recently-crowned Wimbledon champion was due to play in the second round of the clay tournament before she pulled out on Thursday.

"I was having some pain in my elbow," the world number one told reporters. "I felt it a little bit in my match yesterday, and then it got better, but then this morning I really couldn't hit serves, and if I'm not able to hit serves that could definitely be a problem.

"Unfortunately I haven't had time to heal. I've been going, going, going, playing tournaments I love, and coming here has been such a great joy, but unfortunately it's not going to heal if I keep playing."

Williams thrashed Belgian qualifier Ysaline Bonaventure 6-2 6-1 in the opening round on Wednesday, four days after she beat Garbine Muguruza to win her sixth Wimbledon title.