Raducanu took some time away from tennis and decided to return in California this week, joined by extra security. The world No. 55 admitted the allure of one of her “favourite tournaments” made it difficult to stay away from Indian Wells.

Ahead of her first-round match, the Brit confirmed she would be working with Slovakian coach Platenik on a trial basis. But their new partnership got off to a discouraging start as she suffered defeat on Thursday.

Raducanu had never lost in the first round of Indian Wells. Her worst result previously came in 2021, weeks after her US Open triumph, when she got a bye directly into round two and was beaten.

The 22-year-old got off to a positive start against Uchijima, breaking immediately to take a 2-0 lead. But she quickly lost the next four games in a row.

Raducanu got back on serve, but the world No. 52 broke again and closed out the first set. However, there was already a positive indication of her partnership with Platenik, as commentator and former player Naomi Broady noticed their good communication.

“Even though it is a new relationship, you can see the reaction from Raducanu there after she’s missed,” Broady said on Sky Sports.

“Immediately looking up to the coach, wanting feedback. Coach is giving it. Good communication.”

Uchijima broke in the first game of set two and got out of a tight game to extend her stronghold on the match. The Japanese continued to put Raducanu under pressure, making it a nightmare for the Brit to get out of her service games.

The tide seemed to be turning when Raducanu had three break-back points in a marathon game, but she couldn’t convert any of them and Uchijima continued to move ahead.

The missed opportunities took a toll on Raducanu - she suddenly found herself facing three break points and double-faulted to put the final nail in the coffin, giving her opponent the chance to serve for the match.

Uchijima got the job done, sending the Brit packing and setting up a meeting with No. 3 seed Coco Gauff.

Raducanu is expected to be in action at the Miami Open later this month. It remains to be seen whether she extends her trial with Platenik after an early exit at their first tournament together.