The 2019 Stanley Cup playoffs have been a rollercoaster ride for hockey fans, with a few surprising eliminations so far, and more surprises yet to come as the conference finals kick off tonight. But a century ago, hockey fans and players alike were coping with a very different kind of drama as an outbreak of influenza continued to rage across the globe. 

In the spring of 1919, the Montreal Canadiens and the Seattle Metropolitans were battling it out for Stanley Cup glory at the Seattle Ice Arena. Both teams had won two games, lost two and tied one. But before they could play the deciding game of the series, disaster struck. Several Montreal players and the Canadiens’ manager, George Kennedy, came down with the so-called “Spanish flu,” the fast-moving virus that had begun killing otherwise healthy adults the previous spring. Three members of the Metropolitans also became sick. 

With so many players bedridden or hospitalized, officials were forced to cancel the Stanley Cup final with no winner decided. The only two Canadiens players who didn’t get sick were sent home. Less than week after being hospitalized, Canadiens defenceman Joe Hall died of pneumonia. After the cancellation, Kennedy reportedly tried to award the Cup to Seattle; Seattle refused, and today the Cup displays the names of both teams as the winner for that year. 

It would be 86 years before hockey fans were denied another decisive Stanley Cup victory, during the 2004-05 NHL lockout. 

All in all, the flu pandemic of 1918-19 would kill some 50 million people worldwide — a terrible blow in the wake of the devastation of the First World War. But the outbreak also changed our understanding of how disease spreads, and led to a total overhaul of public health practices in many parts of the world. In 1919, an international bureau for fighting pandemics was even established in Vienna, Austria — the precursor to today’s World Health Organization. 

Related: The outbreak and its aftermath