Prajnesh Gunneswaran made a winning start to the 2020 season but Ramkumar Ramanathan exited from the Apis Canberra International following a first round defeat, in Bendigo, Australia, on Monday.
Prajnesh, India's top-ranked singles player at 122, downed the local wild card Jason Kubler 7-5, 6-3 in the first round of the $ 162480 ATP Challenger event.
The left-handed Indian needed one hour and 28 minutes to oust his rival, ranked 257 on the ATP singles chart.
Prajnesh broke his rival four times and dropped his own serve twice in the contest.
"I served quite well but was a bit rusty at the start. Then I got going. It was a good day. I created a lot of chances and converted enough break points to finish comfortably," Prajnesh told PTI.
"I should have won the second set 4-1 but he did well and I also dropped intensity a bit. I still have some wrist issues but I managed to play with it. I have not fully recovered from the tendonitis that I had got in China towards the end of the year," he added.
Prajnesh will next face 13th seed Japanese Taro Daniel, ranked 106.
Ramkumar, though, had to endure a 6-3, 2-6, 3-6 first round defeat against Finland's Emil Ruusuvuori in a contest that lasted one hour and 27 minutes.
The Indian could convert just one of the four break chances he earned.
Svitolina, Kerber fall at first hurdle in Brisbane
American Danielle Collins stunned former champion Elina Svitolina 6-1, 6-1 in the opening round of the Brisbane International on Monday as Germany's Angelique Kerber also bowed out.
World number five Svitolina entered the match as heavy favourite to progress but looked far from her best and failed to convert any of her four break points in the opening game.
Collins took her chances with aggressive hitting to grab an early break and went on to claim five consecutive games and clinch the opening set.
Fourth seed Svitolina struggled with her first serve throughout the match and Collins targeted her soft second serves to dominate the second set.
After losing the first game, Collins powered through six straight games to seal victory in 56 minutes.
It was a significant result for Collins, who has struggled for form since being diagnosed with rheumatoid arthritis in October.
The victory was Collins's third against a top-10 opponent and will lift her confidence ahead of the Australian Open, where she reached her maiden Grand Slam semi-final last year.
Earlier, home favourite Samantha Stosur upset former world number one Kerber 7-6(5), 7-6(4) in a tight clash between former Grand Slam champions.
Stosur, who has not progressed beyond the second round in nine Brisbane appearances, dazzled in the decisive tiebreaks with a combination of solid first serves and devastating forehands to clinch her first win over Kerber since 2015.
"This is sort of the way I want to be all the time on court," Stosur said.
"I put more pressure on myself than anyone could ever do, because I really know what I'm capable of."
"So sometimes I probably want it all too bad - and then that's when you kind of get hamstrung and don't perform as you want to. But today I certainly feel like I did stay relaxed and composed."
Sabalenka begins Shenzhen title defence with emphatic win
Defending champion Aryna Sabalenka started her 2020 season in style with a 6-3, 6-0 victory over Russian qualifier Margarita Gasparyan in the first round of the Shenzhen Open on Monday.
The Belarusian -- who also won titles in Wuhan and Zhuhai last year -- needed only 71 minutes to wrap up the contest, breaking Gasparyan five times on centre court to advance to the last 16.
"I'm happy to start my season with a two-set win," she said in her post-match interview. "It was a tough match and really tough to start."
"She's a great player and it was tough to play against her. She has strong strokes."
Sabalenka will next face the Czech Republic's Kristyna Pliskova, who beat Romanian Irina-Camelia Begu 6-3, 6-3.
Sixth seed Garbine Muguruza fought back to beat China's Wang Xin Yu 3-6, 6-3, 6-0 while Aliaksandra Sasnovich advanced with a 6-2, 6-3 victory over Germany's Anna-Lena Friedsam.
In a battle between two Americans, Shelby Rogers beat Nicole Gibbs 6-3, 5-7, 6-4 in a match that lasted two hours and 33 minutes while fourth seed and local hope Wang Qiang got the better of Tunisia's Ons Jabeur 6-0, 6-3.
Seventh seed Elena Rybakina of Kazakhstan beat China's Zheng Saisai 6-2, 1-6, 6-2.
Edited by Laxmi Negi