Great Britain's Emma Raducanu and Jack Draper both suffered eliminations from the Madrid Open on Tuesday.
The former was facing Garbine Muguruza's conqueror Anhelina Kalinina in the third round and immediately found herself on the back foot against the Ukrainian surprise package.
Raducanu went down 2-6 to Kalinina in the first set before forcing a third with a reverse scoreline, but Kalinina advanced to the quarter-finals courtesy of a 6-2 2-6 6-4 success.
The US Open champion once again needed treatment during the contest as she failed to post three consecutive victories for the first time since her Grand Slam win, with Kalinina taking two hours and 19 minutes to prevail.
The Ukrainian ultimately advanced to the last eight via a strong backhand with her second match point, forcing an error from Raducanu and setting up a quarter-final showdown with Switzerland's Jil Teichmann.
Jessica Pegula and Sara Sorribes Tormo also set up a quarter-final meeting in the women's singles event on Tuesday, and all eyes will be on Simona Halep's battle with Ons Jabeur in the last eight tomorrow.
Earlier in the day, 20-year-old Draper threatened a shock result against world number eight Andrey Rublev, taking the first set against the Russian 6-2 before an early break from Rublev in set two turned the tide.
Draper could not strike back as he fell to a 6-2 4-6 5-7 defeat to Rublev, who could now face another Brit in Dan Evans in round three, but the youngster's promising performances continued on the clay surface.
"I'm gutted that I couldn't sustain my level and come through the match, but at the same time, this week's a new experience for me, being on the clay in a top event like this and playing a top-10 player," Draper said during his on-court interview.
'I surprised myself a little that I can play a very high level on the clay. I still feel like I've got so much more in me. There is such a long way to go in all areas, which is really exciting."
There were also victories for Novak Djokovic and Marin Cilic on Tuesday, with the former seeing off Gael Monfils in straight sets to set up a showdown with the winner of Andy Murray and Denis Shapovalov's late battle.
