When she arrived in Miami last year, Daria Kasatkina had already won 13 matches and had just played in the biggest final of her career at Indian Wells.
This time, it was a very different story, as she started her second round match in search of only her fourth win of the year.
Encouragingly, the Russian beat 15-year-old star-of-the-future Cori Gauff 6-3 6-2 to give herself something to build on.
But the optimism did not last long. Kasatkina failed to hold serve at any time during her humbling 6-3 6-1 loss to Venus Williams.
It was an extraordinary performance for all the wrong reasons, and it is easy to imagine just how depressed the Russian will be feeling about it.
Furthermore, the ease of the scoreline does not make sense when compared to the players’ three previous encounters.
All those matches, at Wimbledon, Indian Wells and Auckland respectively, were closely-fought contests that went the distance. In addition, Kasatkina won two of them, which makes the contrast even starker.
Given this evidence, it is clear something is not right with the Russian, and she will need to find a way of regaining her form soon to avoid a dramatic slide down the rankings.
Mertens, Sevastova and Collins Crash Out
In February, Elise Mertens produced the best tennis of her life to beat Kiki Bertens, Angelique Kerber and Simona Halep and claim her first Premier title in Doha.
Since then, she has suffered one first-round loss and two second-round losses. The latest of those came today against Marketa Vondrousova.
It was a close encounter, and there was nothing to choose between the two players until the Czech teenager earned a break in the ninth game to move 5-4 ahead.
The second set was even tighter. Both players served better to take it all the way to a tie-break, which Vondrousova won.
Anastasija Sevastova also experienced an unexpected loss. She was defeated 1-6 6-2 6-3 by Yulia Putintseva.
Although she played well in the first set and a half, she was unable to sustain that level throughout the match and her Kazakhstani opponent took full advantage.
Danielle Collins became the third seeded casualty of the day when she lost 7-5 6-1 to rising star Wang Yafan.
The Chinese player has enjoyed an extraordinary recent run of results. She beat Donna Vekic and Sofia Kenin en route to her first WTA title in Acapulco.
Wang then beat Kristina Mladenovic and Elina Svitolina, both in straight sets, to set up a meeting with Collins. In the last 16, she will face the highest-ranked player from her country: Wang Qiang.