The 19-year old Ecuadorian winger scored a goal and provided an assist in the club's 2-1 win over Houston Dynamo at BMO Field on the weekend.
He opened the scoring in the 49th minute with a neat finish from the penalty spot before sliding a lovely ball from the left for Maicon Santos who put the ball home making it 2-0 in the 81st minute.
Plata becomes the fifth MLS first-year player to pick up the award this season.
2011 MLS PLAYER OF THE WEEK WINNERS
Week 1: Omar Bravo (Sporting Kansas City) Week 2: Javier Morales (Real Salt Lake) Week 3: Camilo (Vancouver Whitecaps) Week 4: David Ferreira (FC Dallas) Week 5: Luke Rodgers (New York Red Bulls) Week 6: Landon Donovan (LA Galaxy) Week 7: Will Bruin (Houston Dynamo) Week 8: Joao Plata (Toronto FC)