"It's a great accomplishment obviously," Harden said. "I have a bigger picture and bigger goals, but it's pretty cool."
Teammate and longtime friend Russell Westbrook, who also played in the game in which Harden got the first points of his NBA career, was much more effusive in his comments about the milestone.
"To be able to do that on a very, very high level is something we don't take for granted," Westbrook said. "Growing up in L.A. and being able to see him progress over the years, to me, is just a blessing to see as his friend, and I'm truly happy for him.''
Not everything went smoothly for Harden, though, as he turned the ball over 11 times in the first half, marking the most turnovers in a half by any player in the past 20 seasons, according to ESPN Stats & Information. The only other player to have 10 in a half in the past 20 seasons was Gilbert Arenas on Nov. 10, 2009, in the second half against the Heat.
Harden became the first player this season with a points-rebounds-turnovers "triple-double," and he did it by halftime. It was done five times in a game last season.
Saturday marked Harden's sixth career game with 30 or more points and 10 or more turnovers -- twice as many as that of any other player in NBA history.
Harden, who had 12 rebounds and eight assists, is the 45th player in NBA history to reach 20,000 points and the seventh-youngest. He entered the game 10 points away and reached the milestone in fitting fashion: on a step-back 3-pointer midway through the second quarter.
The public address announcer simply said 20,000 after Harden hit the shot, before a video was played during the next timeout to mark the occasion. The video showed Harden making his first points in the NBA while with the Thunder, then making a free throw that gave him 10,000 points and a replay of the 3 that got him to 20,000.
Harden got the game ball on Saturday and presented it to his mother.
"She has everything,'' Harden said. "Every goal and achievement that I have, she has it. I gave it to her, and she'll put it in a safe place.''
Already without Clint Capela because of a bruised heel, the Rockets lost fellow starter PJ Tucker early in the first quarter, when he fell hard on his right shoulder. Houston was just fine without them, thanks to another big game from Harden and a 30-point, 6-rebound, 10-assist performance by Westbrook.
Harden and Westbrook became the first pair of Rockets teammates to each have 30 points, 5 rebounds and 5 assists in a game since Hakeem Olajuwon and Robert Horry on April 14, 1994.
Houston led by double figures for most of the game and used a huge run in the third quarter to put the game out of reach and bounce back after a lopsided loss to Oklahoma City on Thursday.
The Associated Press contributed to this report.