The Sarasota, Florida crowd at the Orioles' spring-training home treated Mancini to a standing ovation that lasted nearly a minute before his first at-bat. The visiting Pittsburgh Pirates also joined in on the applause.
"It was amazing," Mancini said, according to Jon Meoli of The Baltimore Sun. "I almost teared up a little bit, I'm not going to lie, when I was up there, and everybody gave me a standing ovation, and I saw all the guys on the field clapping on the Pirates, clapping in the dugout, our team, and all our fans.
"It meant the world to me. It was a really, really cool moment and one of the favorite moments of my baseball career. I think it was a huge day for me, personally, getting back in a game. Just another kind of milestone that I can check off here."
Orioles manager Brandon Hyde added that it was a "goosebumps moment."
Mancini was coming off a breakout 2019 campaign, hitting 35 homers over 153 games. When he reported for camp last year, his physical showed an irregularity, and further tests found a malignant tumor in his colon. The 29-year-old wound up missing the entire 2020 season, undergoing surgery in March followed by six months of chemotherapy.