Twenty players have received invitations to attend the 2019 NBA draft and sit in the green room, sources told ESPN.

Zion Williamson, Ja Morant, RJ Barrett, Darius Garland, De'Andre Hunter, Jarrett Culver, Coby White, Cam Reddish and Jaxson Hayes received the first batch of invites on June 7, sources said, with an additional 11 invites sent out over the past week to Sekou Doumbouya, Nassir Little, Rui Hachimura, Brandon Clarke, Romeo Langford, PJ Washington, Goga Bitadze, Tyler Herro, Keldon Johnson, Nickeil Alexander-Walker and Bol Bol. USC's Kevin Porter Jr. and Georgia's Nic Claxton, and FSU's Mfiondu Kabengele were invited this week as well.

The green room is a staging area in front of the NBA draft podium where players, families and agents await commissioner Adam Silver to call a player's name upon selection. Editor's Picks 2019 NBA mock draft: Last-minute intel on all 60 picks

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The process of deciding which players to invite to the draft involves communication with general managers of teams picking throughout the first round. This is to ensure that players aren't sitting for very long under the bright lights before a national television audience as the second round approaches.

Receiving an invitation is considered a positive sign for a player's draft stock, although there have been instances in the past of prospects falling to the second round while sitting in the green room.

Nineteen of the players invited were projected to be picked in the top 20 of the latest ESPN mock draft, with the lone athlete not in that group, Keldon Johnson, projected at No. 23.

Seven of the players invited to the green room were born outside of the United States, believed to be the second-highest number behind the 2016 NBA draft, which had eight such invites and eventually broke the all-time record with 26 total international players drafted in both rounds.

Here's the full list of invites: