Arthur was waived by the Suns on Monday, Shams Charania of The Athletic reports.
Arthur was traded to the Nets on Thursday, Adrian Wojnarowski of ESPN reports.
Arthur exercised his $7.4 million player option for the 2018-19 season Friday, Shams Charania of Yahoo Sports reports.
Arthur will start at power forward for Tuesday's game against the Spurs.
Arthur (coach's decision) didn't see the floor in Wednesday's 134-111 win over the Suns.
Arthur (knee/illness) is not listed on the injury report in advance of Sunday's preseason contest against the Spurs, Adam Mares of DenverStiffs.com reports.
Arthur (knee/illness) was unable to play in Monday's preseason game against the Lakers.
Arthur (knee/illness) did not play in the Nuggets' preseason opener Saturday.
Arthur (knee) is dealing with a stomach issue which has been plaguing him since he returned from Germany to undergo PRP therapy, Chris Dempsey of Altitude Sports reports.
Arthur (knee) will face limitations to begin training camp, Harrison Wind of BSN Denver reports.