Ana Ivanovic, an extremely popular figure in Beijing, was among the first round winners on Saturday.
Li Na led the Sunday winners, then autographed some kids' drawings of her after her press conference.
Also Sunday, Jelena Jankovic beat Andrea Petkovic in a match between friends and doubles partners.
World No.1 Victoria Azarenka took the court for her first round match on Monday, facing Alize Cornet.
Victoria Azarenka passed her first test with flying colors, beating Alize Cornet in 66 minutes, 61 60.
Victoria Azarenka was broken in the opening game but won 12 straight games to beat the Frenchwoman.
World No.2 Maria Sharapova followed the World No.1 onto center court for her own first round match-up.
Maria Sharapova battled her way to a tight two set win against talented Romanian Simona Halep, 75 75.
Simona Halep was punished by Maria Sharapova on her second serve, winning just nine of 27 points on it.
Meanwhile, Maria Sharapova won over half of her second serve points - 14 of 25 - en route to victory.
Former Top 20 stars Anabel Medina Garrigues and Sabine Lisicki also met Monday - Lisicki won, 63 57 62.
Li Na was on her game as she faced Nadia Petrova in the second round, beating the Tokyo champ, 61 62.
Li Na had only taken one set off Nadia Petrova in six previous meetings but this time was very different.
Victoria Azarenka punished the Sabine Lisicki second serve en route to a 64 62 second round victory.
Julia Goerges pulled off the biggest surprise of Day 4 on Tuesday, upsetting No.8 seed Samantha Stosur.