Houston (CBS HOUSTON) – Sunday’s Lone Star showdown and a rematch of last season’s first-round playoff meeting didn’t disappoint.

The Rockets and Mavs traded game-changing runs and some chippy play to boot, but the Rockets ran away in the fourth quarter to score a 115-104 win in the Toyota Center.

It was further proof that, with Josh Smith back in the fold, the Rockets might just be having fun again after a dreary first half of the season. When Smith fooled Dirk Nowitzki on a pump-fake hook shot to put Houston up 12 in the fourth quarter, the raucous bench celebration may as well have been straight out of last year’s postseason push.

“It was a fire that was there; You could see it burning,” head coach JB Bickerstaff said. “The energy was there. It was a great enthusiasm. When everybody’s a part of it, everybody’s connected, that’s the difference for this team. I think we’re starting to find that.”

Trevor Ariza has found his shooting form of late, and he followed up five three pointers on Friday with a 29-point outing, 17 of them in the first quarter. Former Rocket Chandler Parsons led the way with 31 points and six rebounds for the Mavs.

It’s just the third time all the season the Rockets (24-22) have been two games above .500.

“The fun is definitely back,” said James Harden, who notched his second triple-double in three games.

Dallas grabbed a 10-point lead midway through the third quarter, temporarily stunning a newly-confident Rockets bunch. Ariza and Patrick Beverley, who was back after missing two games with an ankle injury, immediately drained three-pointers to kickstart an 11-1 run that left the game up for grabs entering the fourth.

The Rockets pummeled their in-state foes down the stretch, riding hot hands beyond the arc and some transition buckets to a 31-point final-period blitzkrieg. And who else was riding in the middle of it but the newly-acquired former Rocket, J-Smoove?

Smith drained a key 3-pointer, threw down a massive dunk and completely baffled Nowitzki on the aforementioned pump fake. With Smith on the floor, the Rockets have looked like a different team passing the ball in consecutive games. They’re cutting to the basket with efficiency, thanks to a versatile big man with considerable passing ability back in their arsenal.

“I am a pass-first kind of player, so being able to break the defense down or get into a pick and roll with James and being able to catch a ball going downhill and seeing shooters is always beneficial,” Smith said.

Of course, it makes his job easier when he has such a slippery guard like Harden to feed off. Harden earned the triple-double on 23 points, 15 rebounds and 10 assists.

In four games this past week, Harden averaged a 23-10-10 line. The star guard appears renewed by Smith’s addition and Ariza’s hot shot.

“It’s just perfect timing,” Harden said.

The Rockets jumped out to a sizeable first-quarter lead, piling up 36 points for their third straight 30-point opening period.

“The way the game started, I thought we locked in really well, and we stayed locked in for the majority of the game,” Ariza said. “The ball flow was great tonight, and we feel like that’s the way we’ve got to play.”

The Mavs more than doubled the home team up in the second quarter, taking a 58-50 advantage into the locker room.

But the Rockets were deeper — even without Dwight Howard again — getting 16 points from Smith while Ty Lawson added 10 more off the bench.

“A couple of stops in a row, a couple of good possessions, and our rhythm is right back,” Ariza said.

Houston, now 15-11 at home, pulled within a game of Dallas for sixth place in the Western Conference. The Rockets are also just 1.5 games back of Memphis for the No. 5 seed.

They start a three-game road trip on Monday night with a visit to the Pelicans.