British second seed Alfie Hewett lost to Belgian Joachim Gerard in three sets in the quarter-finals of the men's wheelchair event at Wimbledon.
French Open champion Hewett, 23, was beaten 7-5 3-6 6-3 by Australian Open winner Gerard.
Two-time semi-finalist Gerard saved set point before breaking Hewett in the 11th game and serving out the opener.
The Briton responded in the second set but an early break was enough for the Belgian to clinch the decider.
Five-time Grand Slam champion Hewett, who won two silver medals aged 18 at the Rio Paralympics in 2016, is targeting two gold medals at the Tokyo Games this year.
World number four Gerard will meet France's Stephane Houdet or Dutch wildcard Tom Egberink in the last four.
In the other half of the men's draw, Hewett's doubles partner Gordon Reid - the 2016 singles champion - begins against Japan's world number one Shingo Kunieda on Thursday.
In the women's event, Britain's world number four Jordanne Whiley meets the Netherlands' Aniek van Koot and compatriot Lucy Shuker faces Dutch top seed Diede de Groot.
Meanwhile, Andy Lapthorne, quad wheelchair singles finalist in 2019, opens against US Open winner Sam Schroder.