The Wizards, unfazed, responded with a 14-0 run and beat Oklahoma City 97-85 on Friday night.
''I told the guys that's why the fans are going to fall in love with our team - because we give a lot of incredible effort,'' Wizards coach Scott Brooks said. ''I mean, it's maximum effort every time on the court, and some of the time, you don't know what's going to happen.''
Oklahoma City shot just under 40 percent, made just 14 of 22 free throws and had 19 turnovers.
Gilgeous-Alexander scored a career-high 28 points and Danilo Gallinari added 18 for the Thunder. Point guard Chris Paul, who scored six points in 30 minutes and had four assists and five turnovers, blamed himself for the loss.
''If I would have contributed at all we would have won the game, and that's something, and you can't sugar coat it,'' he said.
The Wizards led 52-46 at halftime, then scored the first six points of the second half. The Wizards led 78-70 at the end of the third quarter.
The Thunder held the Wizards scoreless for the first 4 1/2 minutes of the fourth quarter to tighten the game. Gilgeous-Alexander's mid-range jumper tied it at 83 with 4:26 to play.
Washington responded quickly. A 3-pointer by Davis Bertans put the Wizards up by five, and a layup by Beal forced a Thunder timeout. The Thunder made just one more basket the rest of the way, and that came with 20.9 seconds remaining.
Brooks said Washington is improving because the team's young players have the right attitude.
''It's hard to teach when you have students who aren't interested in learning,'' Brooks said. ''I love the group that we have. We want to get better, and that's a coach's dream.''
Wizards: G Jordan McRae sat out with a finger injury. He played 23 minutes in the opener against Dallas. ... Ish Smith, who had a short stint with the Thunder, started the game and finished with four points and five assists. ... Beal made 4 of 17 shots the first three quarters but 3 of 5 in the fourth.
Thunder: G/F Andre Roberson did not play, and Oklahoma City coach Billy Donovan said he doesn't know when the defensive stopper will return to action. Roberson has missed the past 1 1/2 years while recovering from surgery on his left patellar tendon. ... Starting shooting guard Terrance Ferguson did not take a shot for more than 1 1/2 games to start the season. He has scored two points in two games, both starts.
Thunder C Steven Adams is off to a rough start. The 7-foot center from New Zealand has made 4 of 17 field goals and 2 of 8 free throws the first two games. He's averaging 12.5 rebounds, but his offensive struggles have hurt a team that has been in two close games to start the season.
Adams, talking about a Thunder team that has three new starters since last season: ''Just chemistry, mate. Just chemistry, get a bit more flow. It's just constantly building. This stuff ain't easy.''
Paul took a different approach.
''It's the NBA, we are all pros,'' he said. ''You can't be taking time and losing games.''
Wizards at San Antonio on Saturday night.
Thunder: Host Golden State on Sunday.
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