HOUSTON -- Most of the Houston Rockets’ headliners watched their words carefully this week regarding the replacing of Chandler Parsons, who will return to town this weekend with the rival Dallas Mavericks.

Center Dwight Howard danced around the subject, saying he didn’t want to compare Parsons and Trevor Ariza, who filled the Rockets’ void at small forward with a much more cap-friendly contract than the three-year, $46 million deal Parsons signed with Dallas.

Rockets general manager Daryl Morey, who offended Parsons with his July explanation of the Rockets’ decision not to exercise their right to match the Mavs’ offer to the restricted free agent, simply declined an interview request via Houston’s media relations office.

However, shooting guard James Harden responded to a question about how Ariza has changed the dynamic in Houston with the ruthlessness of one of his basket attacks, certainly not shying away from contact, perhaps even seeking it.

“His leadership, his defensive abilities, his shot-making -- all three of those things are something that we were lacking last year,” said Harden, who ruffled Parsons’ feathers this summer when he downplayed the impact of the small forward’s departure, describing himself and Howard as Houston’s cornerstones and the rest of the roster as role players. “[Ariza] brings that ability to the table this year.”

The Mavs, who are 10-3 and have the NBA’s best offense entering Saturday night's game against the Rockets, unquestionably became a better team because of Parsons’ move up Interstate 45. Can the 9-3 Rockets make the same claim? The early results suggest that's the case.

Parsons, for the record, says he hopes Houston does well but doesn't concern himself with how Ariza fares filling his shoes.

"I don't pay any attention to him," Parsons said recently. "Listen, many people replace many people every year in this league. He's a good, proven player in this league. He's supposed to play good for them."

Ariza’s intangibles, by definition, can’t be measured against Parsons’. Ariza, who is averaging 14.5 points and 2.6 assists while shooting 41.9 percent from the floor and 39.2 percent from 3-point range, hasn’t matched Parsons’ offensive production from last season other than slightly better 3-point shooting. But there’s no denying the defensive impact the 6-foot-8 Ariza has made for the Rockets.

Houston has gone from decent to dominant defensively. The Rockets, with Ariza joining Howard and point guard Patrick Beverley as proven stoppers in the starting lineup, have the league’s stingiest defense so far this season.

Houston ranked 12th in the NBA in defensive rating last season, allowing 103.1 points per 100 possessions. That number has plummeted to a league-low 94.3 after 11 games -- 92.5 with Ariza on the floor.

“I’ve been able to instill some of the beliefs that I’ve had throughout my career here as well as understand what they already do and try to build on that,” said Ariza, a 10-year veteran who has no issue with being characterized as a role player. “I think that’s something that our staff has always believed in but this year we’re focusing on more.

“Me being a player that throughout my career I’ve been known to be a defensive player or presence or whatever the case may be, it just helps out a lot. And it’s been a great fit so far.”

It certainly isn’t how Morey hoped to piece together the Rockets’ starting lineup this summer. The plan was to add a proven All-Star in free agency and then exceed the salary cap to keep Parsons.

Houston had to go to Plan B when Chris Bosh surprised the team by re-signing with the Miami Heat and the Mavs gave Parsons a much more lucrative offer than the Rockets anticipated the restricted free agent receiving.

At that point, Morey made the call to prioritize cap flexibility over continuity, essentially declaring that he didn’t believe Parsons would blossom into the third star the Rockets need to maximize their championship chances. By signing Ariza to a four-year, $32 million deal, Houston replaced Parsons without sacrificing its chance to pursue an All-Star again next summer.

(Get ready for the Rockets-Mavs rivalry to heat up again over the offseason, when they’re both positioned to be at the front of the line for free-agent-to-be point guard Rajon Rondo, among others.)

“It came down to a bet of Harden, Howard and Parsons being the final piece, because we would have had no ability to do anything after that,” Morey said on Sports Talk 790 AM in Houston the day that Parsons’ deal with Dallas became official. “And Harden, Howard, Parsons could have been good enough. I think Parsons is a tremendous player and is going to keep getting better.

“The question is, is it better with that core or is it better with Ariza plus the hundreds of moves that might be able to upgrade us in the other scenario?”

Perhaps at some point the Rockets will miss Parsons’ offensive versatility, which the Mavs valued so much. Maybe that time has already come.

The Rockets, who also dumped guard Jeremy Lin and his double-digit scoring average this summer to create cap room for Bosh, have averaged only 85.5 points over the past four games, a span in which Houston is 2-2 with close, low-scoring wins over the 0-11 Philadelphia 76ers and 3-10 Oklahoma City Thunder.

Of course, Parsons didn't exactly explode out of the gates in Dallas, fighting through the worst shooting slump of his career. His numbers -- 14.5 points, 41.9 field goal percentage, 34.7 3-point percentage, 2.4 assists -- are significantly down from last season and lower almost across the board than Ariza’s this season.

Not that the Mavs, who had the luxury of bidding high because Dirk Nowitzki gave them a historically steep hometown discount, have any buyer’s remorse. They still view the 26-year-old Parsons, who has been a key cog in the league’s most efficient offense by far, as a terrific fit with huge upside.

“They’re both top-shelf small forwards,” Mavs president of basketball operations Donnie Nelson said. “You could sit here and compare apples and oranges, but they both put their own unique stamp on the position.

“We both came away with probably our best-case scenario at the small forward spot.”