OKLAHOMA CITY - Whether it’s ill-advised shots, poor defense or just bad luck, the Oklahoma City Thunder will need to avoid their early-game meltdowns if they’re going to win the NBA championship.In the series opener of the best-of-seven NBA Finals against the Miami Heat on Tuesday, the Thunder trailed by 13 in the first half before rallying to win 105-94.On Thursday, an 18-2 deficit the start the game was too much to overhaul and the Thunder lost, 100-96, to suffer their first postseason home setback this year after nine straight wins."Well, we missed some shots,” said Thunder coach Scott Brooks. "We took some bad shots, but we also missed some shots. It’s going to happen."You’re not going to make every shot, but we have to do a better job of coming out with a defensive toughness. That’s what we’ve done all year.”The Thunder staged a furious fourth-quarter rally, coming back from a 13-point deficit in the final nine minutes and had a chance to tie the game in the final seconds.But Kevin Durant, who had 16 points in the final quarter, missed a five-footer and the Heat’s LeBron James was fouled as he grabbed the rebound. He hit the two foul shots to seal the triumph and silence the 18,000 crowd at rowdy Chesapeake Energy Arena.Although the Thunder made a game of it, they admitted it was tough to come back after trailing by so much so early."They established their game and they played attack basketball right from the very start, and they had us back on our heels,” said Brooks."And then we took some bad shots. They were getting opportunities in the paint, wide open threes. It’s tough to overcome when you have a bad start.”Durant, the NBA’s three-time reigning scoring champion, finished with 32 points but had only two in the opening quarter and just six at the half."Oh, man, that was the game,” he said. "We can’t start off down 18-2. Thinking about it, though, we got some good looks. We missed a few chippies, lay-ins, but we can’t get down that much, especially at home."We’ve got to correct it. We’ve got to just stay positive, man. That’s the whole deal. We’ve got to come ready Game Three.”Durant’s team mate, guard Russell Westbrook, finished with 27 points but had only three in the opening quarter on one of seven shooting."I just thought I was playing my game, got easy shots that I usually make, lay-ups, just playing my game,” he said softly. "Just unfortunately the shots weren’t falling.”Brooks said he was more concerned with his team’s sluggish play in the first quarter than Durant’s missed shot in the final seconds, where there was clearly contact with James."I’m going to focus on the first six to eight minutes of the game,” he said. "That’s more important than the last minute of the last play of the game. You know what, he missed a shot.”Game Three is on Sunday night in Miami.