HEY MAVS FAAAAANS (Photo by Christian Petersen/Getty Images)
More as the story develops...
Sources said that O'Brien received a multi-year deal, with Carlisle about to enter the first season of a new four-year extension.
O'Brien was fired by the Pacers halfway through the 2010-11 campaign after three non-playoff seasons in Indy. He previously coached the Boston Celtics (reaching the Eastern Conference finals in 2002) and the Philadelphia 76ers (for one season in 2004-05).