A day stacked with action on both the ATP and WTA side of the draw, we take a look at the Schedule of Play in more detail and preview the top ties.
One of the main ties starts proceedings off on the Estadio court in Heather Watson the number seven seed; taking on Kateryna Bondarenko of Ukraine.
The former is one of the tournament favourites against the veteran who despite being well known is only a few months out from having her second child; she hasn't been able to capture any form of note compared to the Hobart semi-finalist.
Katie Boulter begins proceedings on the Cancha 3 court and after yesterday's brilliance will hope to continue that today and potentially join her fellow Brit in the Quarter-Finals results pending. She defeated Francesca di Lorenzo coming from a set behind; she has another higher ranked opponent next in Zhu Lin.
Many though despite Boulter not exactly playing to her A game as of yet will back the upset. For the Leicester player, she will hope that she can put in a defining run that will get her back to where she was a year ago when she breached the top 80 in the world.
Leylah Fernandez, the young Canadian who has shown so much promise follows that and she takes on Nao Hibino. The latter who is eighth seed has had less time on court as of late reaching the semis in Thailand; but easing past her first round quite comfortably.
While for Fernandez she has had matches in both qualifying and main draw; meaning she could be favoured; but Hibino might be more fresher and that could pose the difference.
Other matches include Tamara Zidansek taking on Kaja Juvan over on Cancha 2 to begin proceedings. Juvan will look to continue her excellent form; which saw her displace Venus Williams and deny the legend; Zidansek though is better on the Head to Head but form could prevail over that.
Another of the top ties sees Tatjana Maria take on Anastasia Potapova, the latter reaching the Quarter-Finals in St Petersburg; also being nestled away on the court mainly reserved for doubles matches, it could be time for the Russian to put in a performance to bring home the title.
Renata Zarazua against Katie Volynets is another intriguing battle. The former dumped out Sloane Stephens and despite the latter not being in form at all, it cannot be taken away; while Volynets defeated Shelby Rogers.
Volynets has shown some real promise in the past with her pushing Bianca Andreescu in her title winning run at the US Open standing out; but home advantage may favour Zarazua here.
Also there is Caroline Dolehide against Christina McHale in an all American affair which could go all the way and Sara Errani making it through to face Chinese ace Xiyu Wang.