Johanna Konta made an excellent first impression for prospective coach Dimitri Zavialoff by defeating Elise Mertens in the opening round of the Kremlin Cup in Moscow.
Konta, who split from coach Michael Joyce last week, defeated the Belgian 6-3 7-5 in less than an hour and a half.
The British number one started confidently, breaking the world number 16 early in the opening set.
Although Mertens looked to rally in the second when breaking Konta in her first service game and then moving 4-2 ahead, the Briton, ranked 44 in the world, responded to break back and level before closing out a victory which included 28 winners.
"I'm obviously really happy with my performance, and to get a win like that against a player like (Mertens) this year is obviously a great boost for me," Konta told the WTA website.
"I'm really happy that I'm just able to set up another opportunity to play another match here."
Konta will next face Daria Gavrilova after the Australian came through Tuesday's late match 7-6 (7/5) 7-5 against lucky loser Vitalia Diatchenko of Russia.
Earlier on Tuesday, Vera Zvonareva beat fellow Russian Irina Khromacheva 6-3 6-3, but another home player Ekaterina Makarova lost 6-1 6-2 against Ons Jabeur of Tunisia.
Kristina Mladenovic of France also progressed after a 6-1 6-3 win over Anna Kalinskaya, while her compatriot Alize Cornet came from behind to beat another home player Natalia Vikhlyantseva, 5-7 6-2 7-5.
Luxembourg Open
German top seed Julia Goerges moved into the second round with a 6-4 6-3 win over Viktoria Kuzmova.
Goerges, the world number nine, will next play Anna Blinkova after the Russian defeated Tatjana Maria 6-2 7-5.
Spain's Garbine Muguruza, the second seed given a wildcard entry, saw off Stefanie Voegele of Switzerland 6-4 6-4.
Tuesday's late match proved an epic three-hour encounter as Ukrainian teenager Dayana Yastremska secured a second-round showdown against Muguruza by coming through 6-2 6-7 (10/12) 7-6 (7/5) against veteran American Varvara Lepchenko.
Yastremska, the 18-year-old world number 66, won her first WTA title at Hong Kong last week, and comfortably took the opening set before Lepchenko, 32, edged a lengthy tie-break to level, forcing the match to go the distance.
Third seed Carla Suarez-Navarro, the world number 24, beat Czech qualifier Kristyna Pliskova 6-3 6-4.
The Spaniard will take on Eugenie Bouchard for a place in round three after the Canadian progressed in straight sets against Hungary's Timea Babos, the world number 63.
Fifth seeded Czech Katerina Siniakova battled through against Sweden's Johanna Larsson, winning 6-1 6-7 (5/7) 6-0 in just under two hours.
Number six seed Donna Vekic also progressed after a 6-0 6-1 win over Anna Karolina Schmiedlova, which set up a second-round match against wild card Fiona Ferro after the Frenchwoman defeated Monica Niculescu in three sets in one of the early matches.
Belgian ninth seed Kirsten Flipkens defeated local wildcard Mandy Minella 6-2 6-3 and will play qualifier Belinda Bencic in round two, the Swiss player beating Dutchwoman Arantxa Rus in straight sets.
