SYDNEY, Australia -- The United States moved to the top of Group C on Day 2 at the United Cup, after securing a 4-1 victory over the Czech Republic.

The Americans went into the day with a 2-0 lead after Taylor Fritz and Madison Keys won their openers on Day 1, and needed just one more win to seal the tie.

Keys, Fritz give USA 2-0 lead over Czech Republic after Day 1

Petra Kvitova kept the Czech Republic's hopes alive in her opening duel with No.3 Jessica Pegula, writing a new chapter in her history of heroics for the Czech Republic. The two-time Wimbledon champion saved seven set points in the opening set to defeat Pegula, 7-6(6), 6-4 to give the Czechs their first win of the tournament. 

The win closed the Americans' lead to 2-1, but the tie ended on an unfortunate note. In the final singles match of the tie, Frances Tiafoe led Tomas Machac 6-3, 2-4 after 89 minutes when the Czech turned his ankle while he was trying to retrieve a forehand. The World No.97 was able to rise to his feet, but after a consultation with the medic and his team, he could not continue and was forced to retire, giving Team USA their third point. 

Kvitova on her win vs. Pegula

It was an unlucky end to a spirited comeback attempt from the Czechs, who looked poised to make things difficult for Team USA. Kvitova led the way in her win over Pegula. The 80-minute opening set was a supreme tug-o-war. Neither player saw a break point through the first eight games of the match, leading to a dramatic finish that saw a combined 13 set points come and go between the two. Pegula gamely saved six set points to hold to 5-5 and then broke Kvitova straight away to earn a chance to serve out the set. 

This time it was Kvitova's turn to come back from the brink. The former World No.2 fired winner after winner from 6-5, 40-0 down to save four set points and break Pegula for the first time, forcing a tiebreak. 

Again Kvitova fell behind and again she roared back. From 5-1 down in the tiebreak, Kvitova went on to save three more set points before earning her eighth set point at 7-6 and finally converting to seal the set. 

"We keep fighting," Kvitova said. "I think USA is such a great team with great players in the team. We are not really favorites here, but we are fighting every match, every point. That's our team spirit."

After her first-set escape, Kvitova broke Pegula twice to build a quick 3-0 lead and managed the closing stages of the set to kick off her 2023 season with a Top 5 win. 

The victory avenges Kvitova's loss to Pegula in the US Open's Round of 16 last fall and extended her edge in their head-to-head to 3-1.

Pegula rebounded from her singles disappointment quickly, teaming up with Fritz to close the tie with a win. The Americans came through in the super-tiebreak, beating Marie Bouzkova and Jiri Lehecka, 2-6, 6-3, 10-7 to finish with a 4-1 win. 

"She did so well putting the returns deep, returning the guys serve, cleaning up so many of those volleys when I was at the back," Fritz said.

"I feel like on our team there's a lot of different options and different pairings and the mixed could be important down the line. We want to figure out what will be our best team or at least get the rust off. The whole thing can be decided by the mixed doubles so we want to know who we want to go with in a big match."

The Czech Republic will face Germany on Saturday. Team USA will have two days off before they close out group play against the Germans.