Tennis-Del Potro withdraws from Miami with wrist injury

MIAMI, March 19 (Reuters) - World number eight Juan Martin del Potro has withdrawn from the Sony Open due to a nagging wrist injury, the ATP Tour said on Wednesday. The injury also forced the 25-year-old Argentine to pull out of the BNP Paribas Open two weeks ago at Indian Wells. In six visits to the Miami event, Del Potro had reached the fourth round three times and the semi-finals in 2009 the same year he claimed his only grand slam title at the U.S. Open. Del Potro claimed his 18th career title in Sydney but has won just three matches since and withdrawn from his last three events. (Reporting by Steve Keating in Miami; Editing by Ian Ransom)