It was a tight affair throughout, with OKC taking a one point lead into the halftime break.
The intensity kicked up a notch in the third quarter as neither side was able to pull away from the other.
Adams showed this when, for the second time in three games, he was given a technical foul for arguing a call with the referee.
Neither side got the better of the other in the third quarter, scoring 22 points each. With 12 minutes to go it was anyone's game - and the two sides played like it.
There was no give in either side as they fought back and forth, trading leads throughout the finial 12 minute period.
It wasn't until the final 40 seconds that the match was won. With the scores tied at 96, Thunder forward Josh Huestis tried to find Adams in the paint but the pass was intercepted. Huestis then committed an unnecessary foul to send Wizards guard Tomas Satoransky to the free throw line, where he nailed both free throws.
That put the pressure on the Thunder to score, but they were unable to. After two more intentional fouls sent the Wizards back to the line, the game got away from the visitors.
The loss saw the Thunder miss a great opportunity to move into the fourth seed in the Western Conference for the first time this season. They went into the match just half a game behind the Minnesota Timberwolves, who lost against the Toronto Raptors on Wednesday.
Had the Thunder won, they would have overtaken the Timberwolves.
Oklahoma City will now have a day off, before meeting the Denver Nuggets in Denver on Friday.
