The Rockets’ lead, once as large as 16 points, was down to five. James Harden, who had dominated the first half, had not scored in the second half. The Bulls, who had blown past the Rockets down the stretch in Chicago, were making another run, this time earlier, but seeming as certain to overtake the Rockets’ once commanding lead.

The Rockets had reached the point of the game when they have often seemed in trouble, with Harden taking a seat to begin the fourth quarter. They had long brought Dwight Howard back in then, but that has not been an option for the past five games and won’t be for at least another month. The Rockets needed a change, and they needed it fast.

That what they got – all kinds of fast. They blocked shots, grabbed rebounds and forced turnovers, running the floor at every change. If Josh Smith or Terrence Jones got a rebound, they were as likely to take it the other way themselves as to pass to Jason Terry. If Corey Brewer or Trevor Ariza forced steals, they looked for the other streaking the other way. If the Rockets had slowed to a crawl to end the third quarter, they had come out flying to start the fourth, building an 18-point lead that took the Rockets past the Bulls, 101-90, with just the style they needed.

“We have to play fast and we have to push the ball,” Rockets coach Kevin McHale said. “When we can get our stops, we can get out and run as long as we can rebound. That group had good energy. They were protecting the basket. They were challenging shooters. And then we were getting out on fast breaks and attacking.

“That start of the fourth kind of put the game away.”

With Howard out, the Rockets said they need to regain their pace more than ever. They scored 20 fast break points against the Bulls, not a particularly large number. But they played with greater tempo, negating much of the Bulls’ significant size advantage.

When the sprint relay team took the floor to begin the fourth quarter, they rushed the lead back to 18 in less than four minutes, seeming to test to see how rapidly they could take a Jones or Smith block or steal into a layup on the other end.