The San Antonio Spurs just couldn't put away the Miami Heat. The Spurs led by 13 with 3:50 left in the third quarter, by five with 28.2 seconds remaining in regulation and by three with 2:42 to play. But the Heat managed to force a seventh game in the NBA Finals by scoring the last six points to beat San Antonio 103-100 in overtime.

LeBron James and Ray Allen each hit three-pointers in the last 21 seconds of the fourth quarter after the Spurs failed to come up with rebounds of missed Miami shots. Kawhi  Leonard went to the line with a chance to put San Antonio ahead 96-92 with 20 seconds remaining in regulation, but he missed the first of two free throws to give Miami new life.

Allen forced overtime by draining his three with 5.2 seconds left following a huge offensive rebound by Chris Bosh.

James was outstanding down the stretch after missing nine of 12 shots in the first three periods. He scored 18 of his 32 points after the start of the fourth quarter and finished with 11 assists and 10 rebounds for his 11th postseason triple-double.

Mario Chalmers scored 14 of his 20 points in the first half, and Dwyane Wade finished with 14 points.

Tim Duncan scored 25 of his 30 points in the first half to help the Spurs take a 50-44 lead into intermission. But he failed to score after converting a three-point play that put San Antonio ahead 68-56 with 4:31 left in the third quarter.

Game 7 is Thursday in Miami.

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