Rising Asian tennis stars Alex Eala and Janice Tjen had a forgettable day at the French Open as both lost in straight sets in Round 1 on Tuesday.Seventeenth seed Iva Jovic defeated Eala 6-4, 6-2 to set up a second-round clash with fellow American Emma Navarro.Jovic earned her first break in the fourth game to move ahead 3-1 and then 5-1. Three double faults from Jovic in the seventh game helped Eala break back. But the Filipina could not find a way back as Jovic clinched the first set 6-4.In the second set, Jovic held serve comfortably and broke again to complete a 6-4, 6-2 victory in one hour and 40 minutes. It means Eala continues her hunt for a first main-draw win in Paris. In fact, she has won only one main-draw match in five Grand Slam appearances.Jovic’s next faces countrywoman Navarro, who defeated Indonesia’s Tjen 6-4, 6-3 in the first round.It has been a rather challenging year for Tjen after the 'Desert Swing'. She has endured first-round defeats in Madrid, Indian Wells, Miami, Charleston and Rome.Meanwhile, world No 1 Aryna ​Sabalenka eased ​through her opening ⁠round at the ⁠French Open as she ​brushed aside Spain’s Jessica Bouzas Maneiro ⁠6-4, 6-2.Sabalenka raced to a 4-0 lead before unforced errors ​crept ⁠into her ‌game, which allowed her opponent ​to pull two breaks back and serve for 5-5.A double fault, however, handed the top-seeded Belarusian the first set and she opened up a 5-0 advantage in the second.Bouzas Maneiro survived another couple of games but ​a double fault ‌gave Sabalenka ⁠victory. “That’s ​the most enjoyable part of ​the ‌game that I can come to ⁠the net to play points ⁠there, it’s so much fun,” last year’s runner-up Sabalenka said.“I’m so happy I was able to improve ​on that part of the game and bring it on court.”Medvedev stalls at start againIn the men's draw, Daniil Medvedev fell to a 6-2, 1-6, 6-1, ⁠1-6, 6-4 loss to Australian wildcard ​Adam Walton.The former world No 1 had fallen at the first ⁠hurdle in six of his previous nine ​appearances ⁠at the clay-court ‌event.Medvedev dropped serve and then allowed Walton to build a 4-2 lead in the opening set which the latter then clinched.The Russian regained his rhythm to wrest control by claiming the next set for the loss of only one ​game, but the sixth seed ‌could not maintain ⁠his grip and let ​the third set slip away.World number ​97 Walton, ‌who was seeking a first win over a ⁠top-10 player, lost the fourth set but fought ⁠on bravely in the decider to break back at 4-4, before completing a famous victory.“It's huge,” Walton said after the win. “I knew I could do it and I believed, so I'm happy with my performance. I'm really excited right now.“It was ⁠such an up-and-down match. I got off to a hot start, and I felt like the ebbs and flows of the match were quite large today. I'm just really proud of my efforts in the ​fifth set, to come from a break down to get the win.”