About a decade ago, Mike Smith tried to capture the sour mood of the patrons in his neighborhood bar, Joe Kool’s. For years, their favorite sports teams endured winless seasons, playoff droughts and epic collapses, so he designed a T-shirt that included a map of southern Ontario with London in the middle and lines connecting to Buffalo, Cleveland, Detroit and Toronto. Above it were the words “The Epicentre of Losing” and a red arrow pointing at London.

Since then, London has morphed into an epicenter of winning, sort of. The Toronto Maple Leafs haven’t won a Stanley Cup since 1967, but have made the playoffs for eight straight seasons (losing in the first round almost every time). Though the Cleveland Browns last won an N.F.L. title the year the Beatles invaded America, the crosstown Guardians have made the American League playoffs six times since 2016.

The real turnarounds, though, are the Buffalo Bills and the Detroit Lions, traditionally two of the N.F.L.’s sad sacks. They convincingly won their divisions this season and, as the playoffs start this weekend, are serious Super Bowl contenders, something that delights their fans in southern Ontario, which separates the two cities.