Down by as many as 14 points, OKC's defense rallied in the second half by limiting Dallas to 15 total points in the third quarter to stay within striking distance.
Sparked by timely shot-making down the stretch including a Chet Holmgren triple to give the Thunder its first lead of the game at 89-86, the tide shifted to OKC with 3:24 left in the game.
When the final buzzer sounded, the Thunder tied the series 2-2 with Monday's 100-96 win in Dallas.
Shai Gilgeous-Alexander led all scorers with 34 points (22 in the second half) to go with eight boards, five assists and two steals and blocks apiece on the night.