9:20pm: The signing is official, according to a team press release.
5:31pm: The Thunder will sign Markel Brown to an Exhibit 10 contract, sources tell JD Shaw of Hoops Rumors (Twitter link).
Brown was the No. 44 overall pick in the 2014 draft, having been selected by Minnesota and subsequently traded to Brooklyn on draft night. He spent two seasons with the Nets before carving out a career internationally.
The Thunder entered the day with four open spots on their training camp roster and 13 guaranteed deals. Training camp in Oklahoma City begins next Monday.