Indianapolis's Marriott Downtown hotel will welcome NFL prospects next week for the league's medical combine after the NCAA tournament ends. INDIANAPOLIS — Three weeks ago, during the second week of March, Big Ten basketball teams started to arrive at the Marriott Downtown hotel for an open-ended stay ahead of the Big Ten and NCAA tournaments, each happening in this city. Not long afterward, this 650-room, 16-floor place transformed into a veritable bubble, completely closed to the public while shielding two dozen teams from much of the outside world for nearly a month. The Marriott Downtown hosted an initial 16 teams during the NCAA tournament’s first weekend, like three other hotels here, before being designated as the home for all those that advanced to the Sweet 16 and beyond. The Final Four participants are the only ones left, each using an entire floor until they’re bounced from the Big Dance. But this bubbled hotel won’t be popped when the national champion and runne