Dodgers manager Don Mattingly said he expects Ramirez will have an MRI on Monday.
"I just jumped and landed on it," said Ramirez, wearing a sling after a 1-0 win over the Chicago Cubs. "I'm not feeling the back of my shoulder. It's really sore and we'll see how it feels tomorrow."
Ramirez is batting .365 with 11 home runs for the NL West leaders. He was hurt in the seventh inning and left the game.
Ramirez fell over a brick barrier and into the stands at Wrigley Field after making a running catch in foul territory. He slumped to the ground in pain and eventually walked off the field holding onto his shoulder.
This has already been a tough year for Ramirez. He's been on the DL while recovering from surgery on his right thumb and for a hamstring injury.
Ramirez said he didn't feel his shoulder pop after this latest injury. Nick Punto replaced him at shortstop.