The second day of the Top Seed Open saw the first round wrap up as the WTA Tour continues it's first tournament in North America with the 31st meeting between Serena and Venus Williams set as both came through their opening round matches.
Cori Gauff advanced as did fifth seed Yulia Putintseva, but fourth seed Amanda Anisimova withdrew before her match against CiCi Bellis while seventh seed Sloane Stephens was knocked out by Leylah Fernandez.
Serena escapes against Pera, Venus dominates Azarenka
Serena fought off a stiff challenge to defeat countrywoman Bernarda Pera 4-6, 6-4, 6-1. It was Pera who struck first, breaking in the fifth game to take a 3-2 lead. She saved a pair of break points and closed out the set with a forehand winner.
Serena dug out of 0-40 to start the second set and that seemed to spur her on, racing out to a 3-1 lead. The world number 108 soon leveled things up and again held 0-40 at 4-4, a point from serving out the enormous upset.
Saving all three chances, Serena then took a 3-1 lead in the final set, saving a pair of break points and she flew through the remainder of the match, claiming final nine points to book her spot against Venus.
Venus picked up her first win of the year with a dominant display, defeating Victoria Azarenka 6-3, 6-2 with a sensational display, particularly on serve and she knew she needed to be on point against the former world number one.
"Having all those first serves going in against Victoria was super helpful", she said. "Vika is an unbelievable returner, so a lot of those serves actually came back with interest, and if you're hitting a lot of second serves against her, then watch out! So I had to play the perfect match against her."
Gauff wins to set up Sabalenka showdown
Gauff battled past fellow American Caroline Dolehide 7-5, 7-5 to set up a blockbuster second-round match against second seed Aryna Sabalenka. Firing off eight aces while winning 80 percent of her first serve points, the 16-year old won 12 of the first 14 points to race out to a 3-0 lead.
Ahead 5-2, Gauff watched as Dolehide saved a set point on her own serve, held and then broke to make it 5-4. A third game in succession levelled the set, but Gauff held and set up two set points with some excellent volleying and she broke with a backhand winner to take a one-set lead.
Dolehide broke in thr opening game of the second set and held her nerve to go up 5-3, but Gauff broke when the qualifier hit a forehand error on break point. Now at 5-5, the Linz champion finished with a flourish, holding with ease and breaking on her second chance as Dolehide flew a forehand long.
"Honestly, I would give it (her performance) an A", she stated after her victory. "It was my first match back since January, and even though I didn't play the best tennis as possible, I think my attitude and effort was an A."
Fernandez dumps out Stephens, Putintseva, Rogers among others to move on
Fernandez beat Stephens for the second time, having beaten the former US Open champion in Acapulco earlier this year. The Canadian won 6-3, 6-3, only broken once in the one hour, 17 minute match, breaking early in each set.
"It felt great being back on court", she said. "Those six months were really hard mentally, not knowing when to start, how to train, how hard to train. I think my team and I did a good job planning and moving forward from there.
"And just being on court again I just had a lot of energy, I felt happier because the competition starts again. Hopefully it'll keep going like this."
Putintseva breezed past Ajla Tomljanovic 6-0, 6-4 and will next face Jil Teichmann, who ousted qualifier Anna Kalinskaya 6-2, 7-5. Fernandez next plays Shelby Rogers, who survived a three-set battle against Misaki Doi, winning 6-4, 4-6, 6-2. Bellis blitzed lucky loser Francesca Di Lorenzo 6-1, 6-2 to advance to play Jessica Pegula.
Anna Blinkova advanced when Kristie Ahn retired, leading 2-6, 6-4, 3-1 when the American called it quits to set up a second round match against Marie Bouzkova. In a matchup of qualifiers, Olga Govortsova knocked out Bethanie Mattek-Sands 7-6 (4), 6-1 and will next face eighth seed Ons Jabeur.