The 35-year-old joins on a free transfer from Genoa.
The two sides will meet in the tournament’s showpiece for the first time since 2018.
17 different players have worn both sets of jerseys during their professional careers.
The Reds are now winless in 16 MLS away matches dating back to last season.
The Reds play four games in 12 days to conclude a month that has already seen them lift their first trophy of the season.
Canada’s talisman bagged a brace as Les Rouges presided over a comprehensive 4-0 victory at BC Place.
The 31-year-old Mexican is reportedly being watched by TFC and two other MLS clubs.
John Herdman’s men will not take the field on June 5th at BC Place amid player compensation issues.
Since the CPL’s inaugural season in 2019, several former Toronto FC players have gone on to represent Forge in the Canadian Premier League.