Atlanta United surrendered another big part of its MLS Cup-winning squad, trading midfielder Julian Gressel to D.C. United on Tuesday after failing to reach agreement on a new contract.

Atlanta acquired $650,000 in targeted allocation money in 2020 and another $100,000 in 2021, with the possibility of receiving an additional $350,000 if Gressel reaches certain performance-based incentives with D.C. United.

The 26-year-old Gressel scored 15 goals and added a franchise-high 35 assists over the past three seasons, helping Atlanta win the league championship in 2018. Last season, he scored six goals and led the team with 12 assists as United won a pair of lesser trophies, the U.S. Open Cup and the Campeones Cup.

Gressel was in the final year of the contract he signed after being drafted in 2017. He wanted a long-term deal and a significant raise, expressing frustration at the lack of progress.

Coming off a season in which they lost to Toronto in the Eastern Conference final, Atlanta United also traded Darlington Nagbe to Columbus and sold defender Leandro Gonzalez Pirez to Tijuana in Mexico’s Liga MX.

Now, with Gressel being dealt away, Atlanta United is undergoing a big overhaul heading into Frank de Boer's second season as coach.

Atlanta United is already in training for its second straight appearance in the CONCACAF Champions League, which begins with a two-legged matchup against Honduras club Motagua that starts on Feb. 18.

The MLS opener is Feb. 29 at expansion club Nashville SC.

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