Near the end of March 2012, Reimer was starting to play to an acceptable standard again, but an upper-body injury (later revealed to be a neck injury) sidelined him for the remainder of the season from March 29. On April 9, he told the media he would be available by training camp in September 2012. Due to the 2012–13 NHL lockout, Reimer was afforded more time to heal and attended training camp in January 2013. Reimer held off an early challenge from rookie backup Ben Scrivens to remain Toronto's starting goaltender. On February 11, Reimer suffered a MCL strain which kept him out of action for a little over two weeks; he won all three of his next starts after returning. Upon returning, Reimer backstopped the Maple Leafs to their first playoff berth since 2004 and finishing the regular season with a career best 2.46 GAA and .924 save percentage in 34 games.