The Houston Rockets declined to match a three-year, $46 million offer sheet for restricted free agent Chandler Parsons, clearing the way for him to join the Dallas Mavericks, league sources told Yahoo Sports.

For the Mavericks, Parsons delivers an impactful free agent to partner on a refurbished frontline that includes Dirk Nowitzki and Tyson Chandler.

Houston ultimately decided the contract would be too crippling for the franchise's cap flexibility and make it more difficult to construct a championship roster around Dwight Howard and James Harden. The terms of the offer sheet, negotiated by agent Dan Fegan, would've had too devastating of cap consequences for the Rockets to match. The contract also has an opt-out clause for Parsons after the second season.

Houston is executing a sign-and-trade agreement with Washington as part of its four year, $32 million deal with free agent forward Trevor Ariza, a league source said.

The Rockets are moving quickly to use the available salary cap space to strengthen roster depth in several areas, especially with the losses of Parsons, center Omer Asik and guard Jeremy Lin.

Parsons has been one of the NBA's most underpaid players in his current deal, which was signed after Houston drafted him in the second round of the 2011 NBA draft. Parsons averaged 16.6 points and 5.5 rebounds for the Rockets this season.

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