After 20 years as a successful car racing facility, interest began to wane and in 1956, Sportsman Park was demolished to make way for what would eventually become one of the nation's premier harness racing tracks under the leadership of Carl Milstein, a well known real estate developer and businessman. Originally constructed in 1934, Northfield Park racetrack was originally known as Sportsman Park, with a focus on midget car racing.

It is owned by Vici Properties and operated by MGM Resorts International. Northfield Park conducts more than 200 harness racing nights each year. MGM Northfield Park (previously Hard Rock Rocksino Northfield Park) is a racino in Northfield, Ohio, U.S.A., a community near Cleveland.