The Toronto Maple Leafs once had to participate in a “play-in” series, and it was awful.
in 2020, after the balance of the season was cancelled, the Columbus Blue Jackets and Toronto Maple Leafs had to play a five game series in order to “qualify” for the proper playoffs.
The series was five games, instead of seven, so luck was a far bigger factor than in the normal playoffs, as seen by Columbus holding the Leafs to under 2% shooting (an NHL record for a playoff series).
This had the effect of making the previous 72 games feel completely meaningless.