EVERETT, WA, USA -- Two Top 10 stars and Grand Slam champions -- 23-time major winner Serena Williams and the newest major titlist Sofia Kenin -- earned victories on Day 1 of the Fed Cup by BNP Paribas Qualifiers to give the United States a commanding 2-0 lead over Latvia, as they fight for a spot in the Fed Cup by BNP Paribas Finals.

Kenin, the new World No.7 and American No.1, extended her winning streak to eight straight matches, as the 2020 Australian Open champion continued her sublime form with a 6-2, 6-2 win over Anastasija Sevastova in the opening rubber.

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World No.9 Williams was forced to work much harder against another Grand Slam champion, 2017 Roland Garros titlist Jelena Ostapenko, but the American legend came away with a gritty 7-6(4), 7-6(3) win to complete an undefeated evening for the U.S.A.

Eight Qualifier ties are taking place all over the world this weekend, to determine the eight nations who will join 2019 champions France, runners-up Australia, wild card Czech Republic and host nation Hungary in the 12-team Finals.

Williams now holds an undefeated 14-0 record in Fed Cup singles matches, though this victory was hard-fought as the former World No.1 had to use all of her vaunted mettle to emerge victorious after one hour and 46 minutes of intense tennis.

The American star took advantage of poorly-timed errors by Ostapenko to earn the first break of the match at 4-2, but two double faults in the subsequent game caused Williams to hand the break right back and put the Latvian back on serve. The duo moved into the tiebreak, where more double faults by Ostapenko helped Williams power her way to a well-earned one-set lead.

Neither player gave an inch in the second frame, as both of the major champions moved through grueling games to 5-5 without a break point up to that point in the set. A stirring backhand down the line in that game finally game Williams three break points, and after another double fault from Ostapenko, Williams held the 6-5 lead.

Serving for the match, though, Williams dropped serve, as powerful returning by Ostapenko pulled the match into another tiebreak. But after a early 0-2 stumble, the depth and power of Williams's groundstrokes came to the fore as she reeled off five straight points to lead 5-2 in the breaker.

Williams eased through the rest of the tiebreak to clinch the whisker-thin win, as the American was sturdier than Ostapenko on second serve, winning 55 percent of those points to the Latvian's 43 percent.

The tie began with Kenin picking up exactly where she left off in Melbourne, with nary a hiccup visible. The newly-crowned Australian Open champion took just 68 minutes to dispatch former World No.11 Sevastova, extending her undefeated record against the Latvian to 3-0.

After an opening two games where the players sussed each other out in lengthy rallies, Kenin started her roll by breaking Sevastova for a 2-1 lead after the Latvian went up 40-0. Down-the-line winners in the early stretches paved the way for dropshot dominance as Kenin grabbed a second break for 4-1, which eased to a one-set lead garnered by a deep forehand winner.

Kenin’s solid returning helped her to an early lead in the second set as well, where she broke Sevastova in the opening game. The cagey Latvian tried to use her excellent arsenal of dropshots and passing shots to pull back into the match, but Kenin was up to the task more often than not, and would be undeterred en route to a 4-1 lead in the set.

Sevastova finally earned her first break point of the match in that game, but squandered it with a long return, and Kenin eased home from there, closing out the win with a love service hold that ended with a forehand crosscourt winner. In addition to saving the lone break point she faced, Kenin won nearly 80 percent of her first-serve points and out-winnered Sevastova by 26 to 12.

Elsewhere, Belgium and Kazakhstan are all square at 1-1 as they battle for a spot at the 2020 Fed Cup by BNP Paribas Finals. Belgium, the 2001 Fed Cup champions, started the weekend off strongly as Elise Mertens gritted out a 1-6, 6-2, 6-1 victory over Zarina Diyas. Mertens won 80 percent of points on the Diyas second serve in the final set, as she eased to victory after the loss of the opening frame.

However, Yulia Putintseva leveled the tie by grinding out a comeback win of her own, as she overcame Ysaline Bonaventure, 3-6, 7-6(2), 6-2, in two hours and 35 minutes. Two-time Roland Garros quarterfinalist Putintseva saved three match points on her own serve at 6-3, 5-3, then fought her way to the win to keep Kazakhstan well in the hunt for a berth at the Finals.

2002 Fed Cup champions Slovakia opened up a 2-0 lead on Great Britain, which began when Anna Karolina Schmiedlova dispatched Heather Watson, 6-2, 6-3. Slovakia had to work much harder to claim the second rubber, but Viktoria Kuzmova eventually grinded out a 6-7(3), 6-3. 7-5 victory over Harriet Dart after nearly three hours of play.

Additionally, two-time Fed Cup champions Germany also got off to a fiery start, as they picked up two straight-set victories to open up their tie against home team Brazil. Laura Siegemund claimed the first match over Teliana Pereira, 6-3, 6-3, while Tatjana Maria followed with a 6-3, 7-6(5) win over Gabriela Ce.

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