For long and impressive stretches of the second half Monday night, Dwight Howard dominated so easily, Celtics coach Brad Stevens might have wanted to send in Sandro Dussek, the 10-year-old in Washington who helped Howard kill time in the rain delays Saturday.

He had given Howard more trouble than the Boston big men.

But that was not the last time the Rockets might have had Washington flashbacks.

The Rockets built another sizable lead, this time taking it to 20, and they let another large chunk of that lead slip away. But after they held on with little difficulty, knocking off the Celtics 104-92, the Rockets thought of the long, strange night in Washington and the win in Boston and believed they are making progress that might finally be built to last.

They reacted to the Boston rally, from down 19 to begin the fourth quarter to within seven, with far greater poise than they had in a panicky fourth quarter in Washington. And for a second consecutive game since their offensive collapse in Atlanta, they ran the offense as they have wanted all along.

The Rockets got the ball inside to Howard in the low post and on the move. They ran their break. They scored 65 points in the second and third quarters, enough to believe they finally might be ready to consistently get their offense — held to 80 points on the first night of the trip — all the way back up to speed.

“We’ve been better at it,” coach Kevin McHale said. “We had some good cutting. We had some good movement. Guys played with each other well. Threes went in because we were able to move the ball and guys can anticipate the ball coming to them so they get their feet set.

“We had some really good ball movement, some really good stuff out there, getting back to how we have to play basketball. It’s nice. We just have to keep doing it.”

The Rockets scored so well once they were through with their 3-of-12 start to the game, they made 46.8 percent of their shots despite clanging their way through the first six minutes and seeing an end to James Harden’s hot streak.