Gwynn Jr. was designated for assignment on July 21.
The 31-year-old was batting just .163 with three RBI as primarily a backup outfielder this season for the Phillies.
Gwynn Jr.'s father, Hall of Fame outfielder Tony Gwynn, died at 54 on June 16. After his father's death, Gwynn Jr. was placed on the bereavement list for eight days. He told John Perrotto of Sports on Earth that it was hard to focus on baseball after his father told him in May that he likely had just a few months to live.
Gwynn Jr. has also spent time with the Brewers, Dodgers and Padres during his eight-year career.
- Sarah Barshop