Pittsburgh police found a 26-year-old woman tied up and crying in Chapman's room when they arrived at the Omni Williams Penn hotel, according to the report.
Chapman wasn't present because the Reds were playing the Pittsburgh Pirates at the time. The game started after a rain delay of 1 hour, 51 minutes.
Officers were alerted by two guests who heard her screaming for help, according to the Post-Gazette. The guests, who were staying on the same floor of the hotel, found the woman inside an open room with her hands bound by cloth napkins, police spokesman Diane Richard said in a news release.
The unidentified woman, whom Richard said was from Silver Spring, Md., was "the hotel guest of a male who attended the Pirates baseball game and who was not present at the time of the incident. During this incident the male guest had various items taken and was later interviewed by detectives," the news release said.
According to the Post-Gazette, the woman told police a man claiming to be a hotel maintenance worker there to fix a toilet knocked on the hotel room door. After she opened it, the man demanded various items in the room, and when she denied him, he bound her and took items including jewelry, a computer, credit cards and ID cards, according to the police department's news release.
The woman was taken to UPMC Mercy hospital.
The Reds acknowledged the incident Wednesday in a statement.
"We are aware of the hotel room robbery of one of our players and we are working with local law enforcement agencies," the statement said. "Because it is an active police investigation, we have no other comment at this time."