Raducanu, 19, looked in fine form as she took the first set against Aliaksandra Sasnovich 6-3.
But the Belarusian Sasnovich dominated the next two sets, limiting Raducanu to just two more games and eliminating her from the second Grand Slam of the year.
Raducanu, who shot to fame at last year’s US Open, has lost in the second round of both of his Grand Slams since the shock victory in New York.
‘I thought it was quite a long match, quite physical as well. I think my opponent played pretty well at all times and didn’t make any mistakes,” Raducanu said after his departure from Paris.
“But yeah, I think it was a long match for me, but I would say the whole clay season has been pretty positive overall.”
Raducanu said he expected to suffer first-round defeats in the four tournaments he played before the French Open, but he did pick up five wins from nine matches in his first season on clay.
“I think I definitely got stronger as the clay season went on,” he added. “It just takes a lot more to win the point on this surface and if you hit the ball flat it doesn’t really do that much.”
‘I definitely learned when to use form and stuff. I still have a long way to go on this surface, but overall I would say I definitely had a good first experience on clay. I think I can definitely improve too.’
Raducanu insists her first full season on the WTA tour will be a learning experience and says developing on and off the court is more important than results.
“I think this year was always going to be a challenge for me to adapt, to find my place,” Raducanu said. ‘It’s going to be much more familiar this time.
‘I feel like in the last 12 months I’ve definitely grown a lot. On and off the court, I feel like I’ve probably gotten better at how much I fight.
“I think that’s one of my biggest strengths and even more so this year, and it definitely opened my eyes to how good everyone is and how deep there is in the game.”
“I think it’s been a pretty positive year just because I’ve learned a lot, and I think the amount of learning I’ve done outweighs any kind of result, to be honest.”
Raducanu will now turn his attention to the grass-court season and return to Wimbledon, where he reached the fourth round last summer before withdrawing for medical reasons.
“It’s going to be really nice to go home and play on their turf, on home grass,” he added.
‘It’s going to be a little weird at first, because I’ve played on clay court for so long it feels like weeks.
‘I’m really looking forward to playing in front of the fans at home, and just to get all that support. Last year I tried a little, but I feel like this year it could be even more. I’m really looking forward to the atmosphere that’s going to be around.’
Raducanu’s loss means there are no British women left in the singles draw, with Heather Watson and Harriet Dart losing in the first round.
In better news for Brits, Cameron Norrie became the first British singles player to reach the third round this year when he beat Australian Jason Kubler in straight sets.
British number two Dan Evans, 32, will be looking to join Norrie in the next round when he takes on Sweden’s Mikael Ymer on Thursday.
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