Sebastien Le Toux remained with United on Tuesday afternoon amid speculation he might depart. (Ted S. Warren/Associated Press)

As D.C. United wrapped up training Tuesday, a dizzying number of deadline-busting roster moves left players and observers alike wondering who would be in uniform this weekend.

Lamar Neagle, traded to Seattle on Monday, was long gone. Bobby Boswell, dealt to Atlanta late Monday, collected his gear and said goodbye Tuesday morning. Sebastien Le Toux continued to practice amid speculation he might depart at some point.

Meantime, Bolivian forward Bruno Miranda, signed late last week, and Hungarian midfielder Zoltan Stieber, signed over the weekend, began to integrate into the last-place squad, even though neither will become eligible until visa and transfer paperwork is complete.

“When you don’t do well and you’re in last place,” captain Steve Birnbaum said, “no one is really safe.”

In another revelation, multiple sources close to the team said United was on the brink of acquiring defensive midfielder Russell Canouse, a 22-year-old Pennsylvania native who has been with Germany’s Hoffenheim and Bochum since 2012.

MLS’s transfer and trade deadline is Wednesday, and none of the 22 teams has been as busy as United (5-14-4), which is both trying to right itself amid a seven-game winless streak (0-6-1) and begin planning for 2018.

Part of that process includes clearing roster and salary cap space. Neagle and Boswell, who were dealt for fourth- and third-round draft picks respectively, accounted for $460,000 combined. Le Toux’s departure would free up another $125,000. All are at least 30 years old, none are full-time starters. Boswell will become a free agent this winter.

While Neagle’s relationship with United lasted less than two seasons, Boswell’s bond was deep. He began his pro career in Washington in 2005 and starred for three seasons before moving to Houston for a six-year stay. He returned to United before the 2014 season via the re-entry draft and captained the squad for three years.

This season, with his role diminishing, he yielded the captaincy to Birnbaum. With Birnbaum and Kofi Opare starting most games, Boswell appeared in 10, all as a starter.

“It’s quick and sudden, but I’m not bitter about it,” said Boswell, 34, who ranks third in MLS history in regular season starts (360). He planned to drive his pickup truck to Atlanta later Tuesday and join a playoff-contending expansion team in need of defensive depth.

His first match in an Atlanta uniform will be Aug. 23 against his former team at RFK Stadium.

“Bobby’s one of my favorite players ever to be around,” United Coach Ben Olsen said. “I was lucky enough to play with him and coach him. He means a great deal to me and this club. So it was a sad day in that sense.”

Birnbaum, Boswell’s understudy when he entered the league in 2014, said: “He’s been great to me. He was a great mentor.”

In his farewell to the team, the personable Boswell said he “tried to make the guys laugh one last time. Just me being me.”

Le Toux, 33, joined United before this season. He has posted two goals in 16 appearances (eight starts) but has logged just 48 minutes in the past six matches. At the end of Tuesday’s session, he was seen having a long conversation with General Manager Dave Kasper.

The departures will allow United to introduce new players, such as Stieber, 28, whose move from Kaiserslautern, a German second-division club, is expected to be announced Wednesday. He has trained with United for two days.

“He’s an exciting piece to have,” Olsen said.

Stieber, who scored for Hungary in the 2016 European Championship, will become United’s highest-paid player with a salary of more than $1 million, sources familiar with the contract said. United will also pay Kaiserslautern a transfer fee exceeding $1 million.

Miranda, 19, is on loan from Universidad de Chile through the 2018 season, with United holding an option to purchase his contract.

“He’s the right kind of kid to succeed in this league,” Olsen said. “It’s not going to happen overnight, though.”

Miranda comes from the same home town (Santa Cruz, Bolivia) and soccer academy (Tahuichi) as United legends Marco Etcheverry and Jaime Moreno. United might loan him at times this season to the second-division Richmond Kickers, Olsen said.

While Stieber and Miranda will address attacking issues (league-low 19 goals), United was also intent on signing a defensive midfielder. It considered Dutch national team veteran Nigel De Jong and made an expensive, but futile, bid to land Inter Milan’s Gary Medel, a two-time Chilean World Cup member.

Now, United appears ready to secure Canouse, who is under contract with Hoffenheim but played on loan last year with Bochum in Germany’s second division (20 league appearances, eight starts, one goal). His lone game in the top-flight Bundesliga came in March 2016 for Hoffenheim vs. Wolfsburg.

It’s unclear whether United would have to pay a transfer fee and what salary Canouse would command. However, even as a Bundesliga prospect, he was probably making much more than the average MLS player.

Olsen and team officials declined to discuss Canouse and other prospective signings.

Discussing United’s broader goals, Olsen said: “We think in some ways we’re solving both [short- and long-term] issues with some of the quality we are bringing in, the age of some of these players. We’ll continued to make moves over the next day or two to make us better now and create momentum going into next year.”

United’s shake-up comes at a time when many MLS teams are increasing spending on player acquisitions and contracts, aggressive initiatives that have begun to leave behind frugal clubs.

“As we look forward, the league is changing,” Olsen said. “It’s getting bigger, faster, stronger. There’s more quality coming in. There’s more money coming in. We certainly, in the short term and long term, will start catching up being a very competitive team in this league.”

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