This is a preseason game, and in preseason Oklahoma City has been two different teams in two different halves. Its first unit has built big first-half leads at home, then the deep bench has handed most of them back after the break. Indiana is built the other way round: its starters play short shifts, but its second unit is made of real NBA rotation players. The final margin depends on who wins the bench half, not on who the champions are.
The pattern is clear in the two home games. Against New Orleans the Thunder led 67-52 at the break, and against Milwaukee, with Gilgeous-Alexander, Jalen Williams, Caruso and Wallace all playing around eighteen minutes, they led 82-64. Both second halves went badly once the two-way players, Exhibit-10 signings and rookies took over: 43-64 and 44-64. Their all-loss form line is mostly summer league with a different roster, but the preseason games share that one cause.
Indiana's second unit is what makes this matchup interesting. Jarace Walker, Sheppard, Huff, Slawson, Toppin and Kobe Brown are players who will be in a regular-season rotation, and they won their second half against Minnesota 62-47 and drew 57-57 with Atlanta. When they face Oklahoma City's deep reserves in the third and fourth quarters, that is the matchup that decides the margin.
The schedule adds to it. The Thunder's deep bench played in Atlanta the night before, with Mara logging 33 minutes, so those same legs are on the second night of a back-to-back. Indiana comes in with three days of rest. Oklahoma City's stated preseason aim is development minutes rather than results, and both teams play again in a few days, so neither coach has a reason to stretch his starters. The case does not rest on any one player sitting out. The rest list for both sides is still open, and Haliburton is a game-day call.
I expect Oklahoma City's first unit to set the tone and lead at halftime, likely by double digits. After the starters sit midway through the third quarter, Indiana's bench should claw that back, and the most common finish is a margin in single digits either way.
That's why I'm siding with Indiana, getting points, rather than picking an outright winner: the Thunder can still win the game while the bench half keeps it close.