Medlen, the Braves pitcher, dropped down a bunt that was fielded by third baseman Placido Polanco. The throw to Morrison drew the first baseman into Medlen.
Morrison went airborne, was spun around and crashed to the ground. Initially he was in intense pain, and the Marlins' training staff rushed to the field.
"I felt like a helicopter," Morrison joked on Wednesday.
Morrison shook it off and played the rest of Tuesday's game. But his hip was a bit sore on Wednesday, and he was given the day off. Conditions in Atlanta are wet, and the Braves started lefty Mike Minor, which also led to the decision to sit the left-handed-hitting Morrison a day.
"I landed on my hip, and I had pain on my hip and my back," Morrison said. "I'm OK now. I'll be fine."
Medlen continued pitching, and he did so with a scrape on his forearm. He told Morrison: "Dude, I haven't had a strawberry since college."
Upon contact, it looked as if both players could have been seriously hurt.
"It did hurt. It was scary too," Morrison said. "I felt like a pop in my back. Obviously you have a shooting pain, but it was fine."
Marlins manager Mike Redmond didn't want to push Morrison back into action on Wednesday.
"He landed pretty hard," Redmond said. "His back has been bothering him a little bit the last week to 10 days. He came in today and he was a little stiff. Get him out of there and give him a day against the lefty and hope he feels better tomorrow."
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter