At the end of the 2014 season, Jack Zduriencik, the general manager of the Mariners, publicly criticized Saunders' work ethic, which Saunders challenged.
On December 3, 2014, the Mariners traded Saunders to the Toronto Blue Jays in exchange for pitcher J. A. Happ.
Saunders agreed to a one-year, $2.875 million contract on January 16, 2015, to avoid salary arbitration.

On February 25, Saunders stepped on a sprinkler head while shagging fly balls and tore his meniscus.
Initially, the expectation was for Saunders to be on the disabled list until the All-Star break.
 However, after having surgery to remove 60% of his meniscus, the estimate was reduced to 4–6 weeks.
He was assigned to the Advanced-A Dunedin Blue Jays for a rehab assignment on April 8.
After the Blue Jays lost 12–3 to the Tampa Bay Rays on April 24, Saunders was activated off the disabled list.
He experienced discomfort in his knee in early May, missing several games after having fluid drained and receiving a cortisone injection.
Saunders returned to the line-up on May 9, but was placed on the 15-day disabled list the following day to rest his knee.
After remaining on the disabled list into August, Saunders was officially shut down for the remainder of the 2015 season on August 18.
He appeared in just nine games for the Blue Jays, batting .194 with three RBI.

On January 15, 2016, Saunders and the Blue Jays avoided salary arbitration by agreeing to a one-year, $2.9 million contract.
In a 13–3 win over the Baltimore Orioles on June 17, Saunders hit three home runs for the first time in his career, and joined Joey Votto, Justin Morneau, and Larry Walker as the only Canadian players to hit three in a game and becoming the first to do it for a Canadian team.
He also had eight RBI in the game, which established another career-high.
Saunders was named as one of five candidates for the All-Star Game Final Vote campaign on July 5.
He was announced as the Final Vote winner on July 8.
After the All-Star break, Saunders struggled to a .178 batting average, eight home runs, and 15 RBI.
Despite the poor second half of his season, Saunders still established several career-highs in 2016.
He ended the campaign with a .253 batting average, 24 home runs, and 57 RBI in 140 games played.
He appeared in eight postseason games for the Blue Jays, and hit .381 with one home run and RBI.
At the end of the 2014 season, Jack Zduriencik, the general manager of the Mariners, publicly criticized Saunders' work ethic, which Saunders challenged. On December 3, 2014, the Mariners traded Saunders to the Toronto Blue Jays in exchange for pitcher J. A. Happ. Saunders agreed to a one-year, $2.875 million contract on January 16, 2015, to avoid salary arbitration.
On February 25, Saunders stepped on a sprinkler head while shagging fly balls and tore his meniscus. Initially, the expectation was for Saunders to be on the disabled list until the All-Star break.  However, after having surgery to remove 60% of his meniscus, the estimate was reduced to 4–6 weeks. He was assigned to the Advanced-A Dunedin Blue Jays for a rehab assignment on April 8. After the Blue Jays lost 12–3 to the Tampa Bay Rays on April 24, Saunders was activated off the disabled list. He experienced discomfort in his knee in early May, missing several games after having fluid drained and receiving a cortisone injection. Saunders returned to the line-up on May 9, but was placed on the 15-day disabled list the following day to rest his knee. After remaining on the disabled list into August, Saunders was officially shut down for the remainder of the 2015 season on August 18. He appeared in just nine games for the Blue Jays, batting .194 with three RBI.
On January 15, 2016, Saunders and the Blue Jays avoided salary arbitration by agreeing to a one-year, $2.9 million contract. In a 13–3 win over the Baltimore Orioles on June 17, Saunders hit three home runs for the first time in his career, and joined Joey Votto, Justin Morneau, and Larry Walker as the only Canadian players to hit three in a game and becoming the first to do it for a Canadian team. He also had eight RBI in the game, which established another career-high. Saunders was named as one of five candidates for the All-Star Game Final Vote campaign on July 5. He was announced as the Final Vote winner on July 8. After the All-Star break, Saunders struggled to a .178 batting average, eight home runs, and 15 RBI. Despite the poor second half of his season, Saunders still established several career-highs in 2016. He ended the campaign with a .253 batting average, 24 home runs, and 57 RBI in 140 games played. He appeared in eight postseason games for the Blue Jays, and hit .381 with one home run and RBI.
Michael Saunders