D.C. United is preparing to trade veteran center back Bobby Boswell to Atlanta United, multiple sources told the Insider late Monday.

Boswell, 34, is in the final year of his contract and, with D.C. at the bottom of MLS’s overall standings, the club has been looking to shake up the roster before the transfer and trade deadline Wednesday. It wasn’t immediately known what D.C. would receive in the trade, but a draft pick seemed most likely.

Steve Birnbaum and Kofi Opare have started the most matches in central defense this year, with Boswell appearing in 10 of 23 games (all starts) and scoring once. He is making $260,000 this year.

Among non-goalkeepers, Boswell is third in MLS’s record books for regular season starts (360) and tied for fifth in games played (365).

He began his pro career with United in 2005 and, after three seasons, served with the Houston Dynamo for six years. Boswell returned to Washington via the re-entry draft before the 2014 season and captained the squad for three years. This season, with his role expected to diminish, he yielded the captaincy to Birnbaum.

Earlier Monday, D.C. traded attacker Lamar Neagle to the Seattle Sounders for a 2018 fourth-round draft pick. Last week, the club acquired Bolivian forward Bruno Miranda on loan from Universidad de Chile, and on Monday, Hungarian national team midfielder Zoltan Stieber (from German side Kaiserslautern) began workouts ahead of a formal signing announcement this week.

D.C. might not be done: Trade talks continue and at least one more signing from overseas is possible.