Before the Dallas Mavericks won the NBA draft lottery and the right to select Cooper Flagg, general manager Nico Harrison was preparing for a pick around the 11th spot.

So, how much more draft prep did Harrison have to do?

"Not too much," Harrison said, resisting the urge to laugh.

The sudden fortune of winning the lottery with a 1.8 per cent chance paid off on Wednesday night (local time) when Dallas took Flagg with the overall No.1 pick, about 24 hours after the Mavs agreed on a new contract with Kyrie Irving.

Ace Bailey, who could have been in the mix to go third but declined to work out for the 76ers, ended up going at No.5 to Utah.

Teen giant Rocco Zikarsky and athletic forward Alex Toohey headline Australia's list of hopefuls in the mix to be picked up when the draft resumes on Thursday (local time).

Nine-time All-Star guard Irving, expected to return from a torn ACL some two or three months into next season, was the top pick out of Duke 14 years ago.

Dallas won this year's lottery on May 12, a little more than three months after the seismic trade of young superstar Luka Doncic to the Los Angeles Lakers for Anthony Davis, a move that enraged most of the fan base.

Irving's injury on March 3 against Sacramento actually played a role in Dallas ending up with Flagg.

It all but ended any realistic playoff hopes for the Mavs, with Davis already sidelined by a groin injury sustained in his Dallas debut a little less than a month before Irving went down.

Davis eventually returned, the Mavs competed in the play-in tournament then lost at Memphis with the No.8 seed in the playoffs at stake. A win there would have kept the Mavs out of the lottery.

Flagg's selection ? considered likely ever since he showed off his considerable game last summer after being invited to the US Olympic team's training camp ? was a daylong celebration in the 18-year-old's home state of Maine.

"It means a lot to me to have the support of the whole state," Flagg said.

"I know how many people showed up today and supported me at some of the draft parties back home.

"It feels amazing knowing I can inspire younger kids.

"I was in their shoes really not that long ago, so just to know I can give those kids those feelings and have the whole state behind me, it means a lot."

with AP