Nick Kyrgios' return to action at the Stuttgart Open ended with a second-round loss to Japanese qualifier Sho Shimabukuro.

Kyrgios, 31, secured his first tour-level win since March 2025 by defeating eighth seed Corentin Moutet in his opening match in Germany on Tuesday.

That was his first singles match since losing in the first round in Brisbane on 5 January.

Wimbledon 2022 runner-up Kyrgios, who has struggled with knee and wrist injuries in recent years, received a wildcard for the grass-court tournament in Stuttgart.

He made a promising start, taking the opening set against Shimabukuro, but his 104th-ranked opponent edged a second-set tie-break and went on to clinch a 4-6 7-6 (7-5) 6-4 victory.

There was no play at the Queen's Club in London on Thursday because of bad weather.

Also in Stuttgart, Taylor Fritz, Jiri Lehecka and Frances Tiafoe - three of the top six seeds - all progressed.

Second seed Fritz, a Wimbledon semi-finalist last year, achieved his first win since the Miami Open in March by battling back against Spanish 20-year-old Martin Landaluce to prevail 6-7 (4-7) 7-5 7-6 (7-3).

Lehecka also came from behind, beating James Duckworth 6-7 (8-10) 6-4 7-6 (7-3), while American Tiafoe won 6-4 6-4 against Rinky Hijikata.

In 's-Hertogenbosch in the Netherlands, top seed Felix Auger-Aliassime beat Marton Fucsovics 6-3 6-4 before rain disrupted the schedule.