The Dallas Mavericks have struck a free-agent deal with guard Monta Ellis, according to sources close to the process.

Sources told ESPN.com that the Mavericks and Ellis have agreed to terms on a three-year deal that -- depending on where Dallas' ends up in terms of salary-cap space as it works on a number of deals -- could rise to as high as $30 million.

The deal, at the minimum, will be in the $25 million range, sources said.

Ellis joins point guard Jose Calderon and former Mavericks guard Devin Harris as free-agent signees in Dallas' overhauled backcourt.

Although it continues to negotiate with free-agent center Samuel Dalembert, according to sources familiar with the talks, Dallas has mostly focused on upgrading its guard play after missing out on top free-agent target Dwight Howard, who went instead to the Houston Rockets.

The Mavericks have also added two highly rated younger players -- first-round pick Shane Larkin and Israeli free-agent point guard Gal Mekel -- to their backcourt rotation.