It may not have been an upset in the same league as last year’s U.S. Open but what happened at the Australian Open on Saturday perhaps wasn’t far off.

Angelique Kerber stunned Serena Williams in a 6-4 3-6 6-4 thriller to open her grand slam account and deprive the American of a 22nd title at a major that would have tied Steffi Graf for the Open Era lead.

Just how rare is it for Williams to lose a grand slam final?

She had won her last eight and was 21-4 overall.