Not only was Williams on the verge of a first clean sweep of the sport 's four Grand Slams in a single year for the first time since 1988 .
Williams would have matched Steffi Graf 's Open - era record of 22 Grand Slam titles .
Not only was Williams on the verge of a first clean sweep of the sport 's four Grand Slams in a single year for the first time since 1988 , but she would have matched Steffi Graf 's Open - era record of 22 Grand Slam titles .