The Hawks selected Doncic with the third overall pick in the 2018 NBA Draft but he will be traded to the Mavericks, as first reported by ESPN reporter Adrian Wojnarowski.
Dallas had been keen on Doncic during the workouts and there was some chatter prior to the draft they were looking at trading up in the draft.
And they have got their man with the Hawks receiving Trae Young in return.
Atlanta will also receive a protected 2019 first round pick.
No other players are said to be involved in the deal.
Doncic is highly regarded as a top prospect having established himself in the Euroleague.
He has been named the EuroLeague MVP and won the championship with Real Madrid this week.
Young has been likened to Steph Curry due to his three-point range.
He is definitely a crowd pleaser and the Hawks will be hoping they have got the best out of the trade.