The 27-year-old Frese hit .243 in 99 games with Iowa in 2003. He missed all of 2004 with a leg injury after falling off a piece of farm equipment at his home in Iowa. This season, he had made only one plate appearance before Saturday's game.
Asked how much he remembered of Saturday's incident, Frese said, "Not much. I get migraine headaches from time to time. All I remember is that I went down off the bench and there I was on the ground. It was a scary deal."
Frese was released from the hospital on Sunday in time for the Cubs' series finale against the Isotopes. He was in good spirits all throughout the day.
"I went to the park to be with my team," Frese said. "Things are better, but my head is pretty sore."
After the incident occurred, initial reports stated that Frese had suffered a seizure.
"I did not have a seizure," said Frese. "The doctors never said anything about that. They ran all kinds of tests and could never verify that. My wife saw those reports and wondered about them."
The Cubs will meet the Round Rock Express for a four-game series beginning Monday night in central Texas. The team's first homestand of the year is scheduled to begin Friday.