The city's education director, Coriolano Moraes, says the measure was introduced because parents were not aware that their children were missing school.
The depleted Blue Jays were missing their two best hitters, Edwin Encarnacion and Jose Bautista, and so it is hard to measure how Pettitte would fare against the best American League lineups.
After missing out on the English title to Manchester United on Sunday, Avram Grant's side have gained a small measure of revenge by beating United in the race to sign Bosingwa, who was also attracting interest from Liverpool and Aston Villa.