Dayton intends to opt out of his contract with the Marlins on Sunday, Robert Murray of FanSided.com
Dayton signed a minor-league contract with Miami in March, and he's posted a 2.51 ERA and 1.06 WHIP in 14.1 innings over 11 relief appearances at Triple-A Jacksonville this year. The southpaw will choose to become a free agent Sunday, likely in hopes of landing a major-league deal elsewhere.