"I didn't tell anyone," he said.
The 24-year-old from Boulder quickly moved the baseball into a safety deposit box after the season was finished, realizing its potential worth. And with Bonds still looking for a place to play this season, Sutton decided to come forward with the ball.
Sutton has hired SCP Auctions to run an online auction that starts March 31 and could fetch as much as $1 million.
"I thought it would be cool to give it to my grandkids, but it's too important of a ball for me to have it in my house laying around," Sutton said Thursday.
Sutton grabbed Bonds' final homer of last season on Sept. 5 at Coors Field when he extended his arm over the fence. He thought he had it cleanly and then was crunched by two other fans.
"I did what was a weird splits, and saw the ball rolling in front of me," he said.
Sutton already had a batting-practice baseball in his hand that he was given by a member of the Rockies' maintenance crew before the game. He let go of that one and snatched the home run ball.
Robert Harmon, who was taking pictures at the time and was close to Sutton, saw a ball rolling and quickly scooped it up. Turns out, he grabbed the batting practice ball.
"When I went back to my seat, I got a phone call from a friend who thought I had the ball," Harmon said. "This kid came up and said, 'My friend got the baseball.' I was like, 'No, I've got it.' I looked at it and was like, 'Oh (expletive).' I've seen enough baseballs to know what a game ball is and what a practice ball is. He's got the ball. I've got a nice souvenir."
Harmon isn't bitter about losing the pricey baseball to Sutton. Being a partial season ticket holder, Harmon has gotten to know Sutton's mom and dad, David and Debbie, who've been ticket holders since the team's inception.
Harmon knows how much the ball can help the family. David Sutton is back in the hospital as he battles cancer. Jameson Sutton has pledged at least half of the ball's proceeds to his parents.
The auction house also handled the sale of Bonds' record-breaking home run ball No. 756, which went for $752,467.
David Kohler, the president of SCP Auctions, said he's already had people say they'll pay up to $1 million for Sutton's baseball.
Earlier in the week, local businessman Gregory Anderson made an offer of $15,000 for the ball. He said he'll take part in the upcoming auction but doesn't know if he'd bid over $100,000.
"We would have to feel really comfortable with a bid that high," Anderson said. "There's too much uncertainty."