Brian Windhorst, Seth Greenberg and Markieff Morris join Mike Greenberg on Get Up to react to the Boston Celtics trading Kristaps Porzingis to the Atlanta Hawks, Kyrie Irving declining his player option with the Dallas Mavericks, how threatening the Mavs will be after drafting Cooper Flagg and more. 0:00 Celtics trade Porzingis 1:26 Irving declines player option 2:23 Biggest threat to the Thunder 2:55 Mavericks to draft Flagg 4:57 "Championship caliber" 7:01 Notable One-and-Dones 7:55 LeBron James on Flagg 8:50 Flagg's fit in Dallas ✔️ Subscribe to ESPN+ http://espnplus.com/youtube ✔️ Get the ESPN App: http://www.espn.com/espn/apps/espn ✔️ Subscribe to ESPN on YouTube: http://es.pn/SUBSCRIBEtoYOUTUBE ✔️ Subscribe to NBA on ESPN on YouTube: http://bit.ly/SUBSCRIBEtoNBAonESPN ✔️ Watch ESPN on YouTube TV: http://es.pn/YouTubeTV #ESPN