The first bet was placed in the newly regulated US state last week, thanks to a partnership between SBTech and Churchill Downs.
The casino located in Pine Bluff, Arkansas, will likely start some operations in the next five months.
Four more applications have been submitted to the state gambling commission to operate casinos in Arkansas.
Two tracks started their operations this week in Arkansas, which has officially debuted its casino market.
The state regulator has given the green light for two Arkansas casinos to launch in the Hot Springs horse-racing track and a greyhound track in West Memphis.