The Thunder were up on the Celtics, 98-92, with 25 seconds left in the fourth quarter. The game was in the bag, just hold on to the lead until the final whistle.

Sounds easy enough, right?

Wrong. Oklahoma City missed three free throws in the final 17 seconds. Terry Rozier waltzed up court and hit a pull-up three. Then Marcus Morris buried a side-step, fading triple that gave Boston a one-point lead with 1.2 seconds left.

This was a terrible loss for the Thunder for many reasons. From a competition standpoint, the Celtics had five key players out with injuries, including Kyrie Irving, Gordon Hayward, Marcus Smart, Jaylen Brown, and Daniel Theis. The Thunder — with its Big 3 fully healthy — should have blown the Celtics out of the water. Instead, they struggled to create separation all game long.

OKC’s defeat has an even more demoralizing impact on its playoff seeding

The Thunder have fallen to 43-30, now 14.5 games behind the No. 1 seed in the West. The thing is, though, the Western Conference is a wild goose chase with seven teams within 4.5 games of the No. 4 seed.

Oklahoma City still retains its standing as fourth in the conference, but the Pelicans are only a half-game behind them. The Spurs, Jazz, and Timberwolves are also in the mix. One or two more losses, and the Thunder could easily find themselves as the eighth seed, destined for a first-round playoff exit at the hands of the Houston Rockets.

The Thunder can’t afford to lose many more games, especially ones against injury-riddled teams missing top players. Hopefully, their loss to the Celtics was a wakeup call. If not, OKC could be gone fishing way earlier than many anticipated.