The Horseshoe, which opened last August, took in $23.1 million from slot machines and table games, a 5 percent jump from May and highest revenue since March, according to the Maryland Lottery and Gaming Control Agency.
The casino was one of several Baltimore attractions that reported drops in business after the late April unrest following the death of Gray, 25, who died from a severe spinal cord injury sustained in police custody.
By comparison, slot and table revenues at the Maryland Live Casino in Anne Arundel County dropped 8 percent since May to $52.9 million.
In June, Hollywood Casino Perryville generated $6.4 million, the Casino at Ocean Downs brought in $5.3 million and Rocky Gap Casino Resort made $3.7 million in slots and table game revenues.
The Horseshoe's revenues inflated the year-over-year revenue numbers for the state's casinos by more than $15 million, but its opening took a toll on the market shares, and the four other casinos that were open in June 2014 saw revenues drop by $3.7 million, or 5.1 percent, the agency said.
A sixth, the MGM National Harbor in Prince George's County, is expected to open sometime in the second half of 2016.