“This is an exciting day for all of us and one that we’ve been looking forward to for a long time,” said MGM Northfield Park President and COO Chris Kelley. MGM resorts, owner-operator of casinos such as Mandalay Bay, Mirage, New York New York, Luxor, Excalibur and Monte Carlo acquired the operating assets of the Hard Rock Rocksino Northfield early this month. NORTHFIELD, Ohio - Northeast Ohio residents and visitors alike can now get a taste of Las Vegas’ nightlife here in Greater Cleveland with the opening of MGM Northfield Park on Wednesday.