The venue was electric as both Williams and Pironkova who are taking their time getting to the best of their tennis. The recent mothers took the court as we watched in awe this two great tennis players battling for a semi final spot in the US Open tournament.
The 32-year-old Bulgarian who was in her first tournament 3 years showed her edginess as she took the first set from Williams who struggled with the shots received from Pironkova.
As done previously in the tournament, Williams took the second set as Pironkova began to tire out on the court.
Serena Williams then broke twice in the third set to take the game away from the Bulgarian tennis star 4-6, 6-3,6-2.
38-year-old Williams looks to face the winner between former world number one Victoria Azarenka and Belgian Elise Mertens.
Williams who is on course to make history has stated that she cannot afford another sluggish start if she is to attain her 24th Grand Slam Singles Title.