San Antonio lead Miami by six points at halftime in Game Six MIAMI (Reuters) - Tim Duncan scored 25 points as the San Antonio Spurs snatched a 50-44 halftime lead over the Miami Heat in Tuesday's Game Six of the National Basketball Association (NBA) Finals. Duncan shot 11-of-13 from the floor as the Spurs overturned a six-point deficit in the second quarter to lead the defending champions by six at the break. Kawhi Leonard scored 10 points for the Spurs while Mario Chalmers led the Heat with 14, including two from behind the arc. Miami's 'big three' scored a combined total of 21, four less than Duncan, with LeBron James contributing nine and Dywane Wade and Chris Bosh six each. San Antonio will clinch their fifth NBA title if they win while Miami will force a winner-takes-all seventh game at home on Thursday if they win. Reporting by Julian Linden; Editing by Greg Stutchbury