Serena was ranked really low since she was out of action for a long time due to injury. But who would want to play her in the early round? I'm sure all the top 4 players wouldn't want her to fall into their quarter draw.
Tier1(goat): Federer; Tier 1.5: Laver, Gonzales, Sampras, Nadal, Borg;
Tier 2: Lendl, Connors, Rosewall, Tilden; Tier 2.5: McEnroe, Agassi