The Boston Celtics have agreed to trade Rajon Rondo to the Dallas Mavericks after more than a year of speculation on the point guard’s future, a person with knowledge of the situation told USA TODAY Sports.In exchange for Rondo and rookie big man Dwight Powell, the Celtics will receive big man Brandan Wright, point guard Jameer Nelson and small forward Jae Crowder, along with the Mavericks’ 2015 first-round draft pick. The person spoke on the condition of anonymity because the trade, first reported by ESPN and Yahoo Sports, has not been made official.The move boosts the Mavs’ weak point guard play, as Nelson and Devin Harris had been splitting time there. The Celtics were eager to move Rondo, who will be a free agent this offseason, and bring in a reasonable haul headlines by Wright, the 27-year-old who leads the NBA in shooting 74.8% from the field as he finally has been able to stay healthy.Rondo, a Louisville native, leads the NBA in assists per game for the third time in four years. His passing skill cannot be doubted, and he has a penchant for triple-doubles as an elite rebounding guard. But his shooting percentage, once an asset at about 50%, has slipped down to about 40% the past two seasons. He is on pace to be the third player in NBA history to average more than 10 assists and fewer than 10 points per game.Trade talks heat up again for Louisville’s Rajon RondoThe four-time All-Star tore the anterior cruciate ligament in his right knee in January 2013. The Celtics traded former costars Kevin Garnett and Paul Pierce to the Brooklyn Nets and allowed coach Doc Rivers to go to the Los Angeles Clippers in the ensuing offseason, and Rondo became a focus of trade rumors even while rehabilitating.Celtics President Danny Ainge has committed to a rebuilding process that included hiring coach Brad Stevens from Butler University and drafting combo guard Marcus Smart sixth overall. This trade is the latest for a team built around young players such as Smart, shooting guard Avery Bradley and big men Jared Sullinger and Kelly Olynyk.Dallas now has a starting lineup of Rondo, Monta Ellis, Chandler Parsons, Dirk Nowitzki and Tyson Chandler, among the NBA’s most formidable units. But the move hurts the Mavericks’ depth, as Wright had been their primary big man off the bench. Greg Smith and Charlie Villanueva now will shoulder more of the burden. Powell, a 6-11 rookie out of Stanford, only appeared in five games for the Celtics.