Despite playing in front of partisan crowds away from home, Belarus and France each had undefeated opening days in World Group first-round action on Saturday.

In Braunschweig, Germany, recent Top 10 entrant Aryna Sabalenka and 2019 Sydney International semifinalist Aliaksandra Sasnovich each claimed a straight-set win to give Belarus a commanding 2-0 lead in their tie against the two-time champion Germans.

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Meanwhile, in Liege, Belgium, Frenchwomen Caroline Garcia and Alizé Cornet opened up their nation's campaign for a third Fed Cup title by grinding through two hard-fought battles to go up 2-0 over 2001 Fed Cup champion Belgium.

Belarus and France are each one match victory away from moving forward into the Fed Cup World Group semifinals, which will take place in April.

Sabalenka and Sasnovich were responsible for the Belarusian Fed Cup breakthrough in 2017, when they propelled their country to its first Fed Cup final after upset victories over the Netherlands and Switzerland. That form was present again as the duo opened the first day of action.

World No.33 Sasnovich opened the tie with a 7-6(3), 6-3 win over 67th-ranked Tatjana Maria, in the first meeting between the two players. Sasnovich had an equal amount of winners and unforced errors in the tilt -- 29 of each -- while Maria could only fire eight winners to 27 unforced errors of her own.

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Neither woman could convert a break point in the first set -- Maria missed both of her chances, while Sasnovich was 0-for-6. In the tiebreak, over half of the points went against serve, but it was Sasnovich who was steelier down the stretch, winning four straight points from 3-3 to earn a hard-fought one-set lead.

The only service break of the match came at 2-1 in the second set, when Sasnovich converted her seventh and final break point. That would be the only one Sasnovich needed as she coolly closed out the match, dropping only two points on serve the rest of the way, after one hour and 38 minutes of play.

“I was very nervous in the beginning because you play for your country and you want to win very much,” Sasnovich said to reporters, following her win. “But I’m happy that I won that match and in the second set I think I show not bad tennis, but I think I can do better.”

Current World No.9 Sabalenka was even more efficient in her 6-2, 6-1 win over former World No.9 Andrea Petkovic, needing only 68 minutes to give Belarus a 2-0 lead.

Hard-hitting Sabalenka crushed 23 winners, including eight aces, to only nine winners for Petkovic. Though Sabalenka had 27 unforced errors as well, Petkovic was also undone by 15 miscues. “I really think [Sabalenka] almost played the perfect match,” Petkovic told reporters. “She rolled over me and was just better in each and every department of the game today."

The cards were not in Petkovic's favor from the outset, as the German dropped her lengthy opening service game on Sabalenka's third break point of the game. Sabalenka cruised from there, hitting four aces and no double faults, to take the first set without facing a break point.

Sabalenka maneuvered to 4-0 in the second set before Petkovic finally got a chance to break serve. The German had four break points in that game, but Sabalenka evaded them all, using two aces to wriggle out of that jam and hold for a 5-0 lead.

Petkovic fired two aces herself to get on the board in the next game, but Sabalenka had no trouble closing out the win in the next game to queue up a substantial advantage for her country as they move into the second day of play.

Things were not as straightforward for the French team. First, 19th-ranked Garcia needed two hours and five minutes to advance past World No.50 Alison van Uytvanck, 7-6(2), 4-6, 6-2. Garcia eked out the victory after being helped by winning a solid 76 percent of points on her second service.

Neither Garcia nor van Uytvanck held a break point in the opening set, necessitating a tiebreak to settle that score. There, Garcia reeled off the first five points in a row en route to a dominant breaker win.

However, van Uytvanck got a handle on Garcia's serve in the second set, breaking the Frenchwoman twice, including at 5-4 to level the match at one set apiece. But Garcia recovered in the decider, jumping out to a quick 5-1 lead, and holding serve at love at 5-2 to seal the first point for France.

Following that, dramatics ensued in Cornet's 7-6(6), 6-2 upset of World No.21 Elise Mertens, in a match which was not nearly as tidy as that scoreline would suggest. Indeed, the two-hour and nine-minute match was longer than Garcia's victory.

At 4-4 in the first set, World No.51 Cornet needed to fend off six break points before holding serve. But Mertens came through two games later, breaking with a stellar angled crosscourt backhand to lead 6-5 and serve for the set. However, strong returning in the following game gave Cornet a break point, and Mertens double faulted, sending the combatants into a tiebreak.

A winning drop shot gave Cornet a 6-3 lead in the breaker, with three set points to come. The Frenchwoman was unable to convert any of those, blasting a forehand error into the net on the final chance and bringing the tiebreak back to parity at 6-6. But a winning backhand down the line gave Cornet a fourth set point at 7-6, where Mertens promptly double faulted again to cede the set.

Cornet was excited to squeak out the first set, which took nearly an hour and a half, and she rode that momentum to a easy second-set win to put France up 2-0. Each player had an equal number of winners and unforced errors, but Cornet got two-thirds of her first serves in, while Mertens hit her mark on the first serve only half the time.