The Miami Heat sustained a gut-wrenching, last-second loss on their third attempt to clinch the Eastern Conference finals, tilting momentum strongly in favor of the Boston Celtics.

However, the Heat, who had to take the play-in route to even reach the playoffs and then upset the top-seeded Milwaukee Bucks to fuel their postseason run, found another gear in their seemingly never-ending fountain of resiliency.

Series MVP Jimmy Butler scored 28 points, Caleb Martin added 26 and the Heat became the second No. 8 seed to reach the NBA Finals by posting a convincing 103-84 victory over the host Celtics in Game 7 on Monday night.