Estrada, who is signed through 2018, would have been eligible for free agency after this season.
The 34-year-old owns a 9-8 mark with a 4.84 ERA and career-best 170 strikeouts in 31 starts this season. He is 31-25 with a 3.81 ERA in three combined years with the Blue Jays.
Estrada, who was an All-Star for Toronto in 2016, joined the Blue Jays in an offseason trade that sent first baseman Adam Lind to the Milwaukee Brewers in 2014. Estrada then re-signed with Toronto after the 2015 season, getting a two-year, $26 million contract.