Game 3 will be crucial. OKC can take the lead in this series for the first time. If they take it I doubt the Pacers have a shot. SO in other words, whoever wins game 5 is in the drivers seat, especially if OKC takes it. Odd on the Pacers to win the series (after losing game 5) will be like 10:1 or something like that.
The winner of the next game will most likely go on to win the championship, especially since Game 7 would still be on OKC’s home court ( if there's a game 7), so all the pressure is on the Pacers. Remember, the Pacers only managed to win on the road because of Hali’s heroic last-second shot and a huge comeback. That didn’t happen in Game 2 and might not happen again.
If the Pacers want to have a real shot, they need to start strong, minimize turnovers, and match OKC’s defensive intensity.
Right now, the series odds for the Pacers are at +450.