D.C. United has waived Brazilian prospect Junior Carreiro, younger brother and teammate of outgoing midfielder Fred.

Junior, 19, severely injured an ankle in preseason and recently returned to active duty. The midfielder didn’t play in any MLS league matches this season after making three brief appearances last year.

“We needed the money [for future roster moves] and I think Junior’s focus right now should be playing games and he’s just not going to get those right now with us,” Coach Ben Olsen said. “For him to progress and be evaluated, he needs some real games.”

Junior was set to earn about $46,000 this season, one of the lowest salaries on the roster. MLS contracts for many players become guaranteed Friday.

Fred, 31, will transfer to Australian club Melbourne Heart in mid-July, a deal consummated two weeks ago. He will remain eligible for United for three more matches: Saturday vs. the Philadelphia Union at RFK Stadium, July 9 at New York Red Bulls and July 16 at FC Dallas.

In other club news.....

*Injury update: Olsen is optimistic that forward Charlie Davies (swollen ankle) will be available Saturday after participating in some of today’s training session.

Defender Jed Zayner, who has missed most of the season with hamstring injuries, is on crutches after spraining his left knee in Tuesday’s training session. He is awaiting further test results.

Defender Marc Burch (hamstring) participated in the full practice session and could be available for selection in the coming weeks.

*Box Seats blogger Jeff Maurer examines the mega-trade that brought Dwayne De Rosario to Washington and sent Dax McCarty to New York.

Before making the trade, United consulted with goalkeepers coach Pat Onstad, De Rosario’s longtime teammate in MLS and with Canada’s national team.

“Pat’s got nothing but good things to say about him,” Olsen said. “Above all, he’s a winner, and we need a personality like him in this team right now.”

With De Rosario’s arrival, United now employs both Houston Dynamo goal scorers from the 2007 MLS Cup final against the New England Revolution at RFK Stadium. Joseph Ngwenya was the other; De Rosario supplied the assist.