Britain's Andy Murray is out of the Surbiton Trophy after American Denis Kudla came back to win in three sets.
Three-time Grand Slam champion and top seed Murray lost 5-7 7-6 (7-4) 6-3.
The former world number one, now ranked 67th, opted to skip the ongoing French Open to focus on his grass-court preparations before Wimbledon.
The 35-year-old is due to play the Stuttgart Open next week and Queen's Club later in June, before Wimbledon starts on 27 June.
Kudla, the world number 81, will play Australian Jordan Thompson or Finland's Otto Virtanen in Sunday's final.
Two-time Wimbledon champion Murray had been aiming to win a first singles title on grass in six years at Surbiton, where he was playing for the first time since 2004.
The Scot made the perfect start in windy conditions, breaking Kudla in his first service game as he opened up an early 3-0 advantage.
The American seventh seed responded in the seventh game - but Murray clinched the first of two set points on Kudla's serve to avoid a tie-break.
A tie-break was required to settle the second set, however, and it resulted in Murray dropping a set for the first time at the tournament.
Murray saved five break points at the start of the final set, but he could only survive one of two against him in the sixth game, as Kudla went on to serve out the match to love.
In the women's draw, Britain's Jodie Burrage fell to a 6-3 6-4 semi-final defeat by Belgian second seed Alison van Uytvanck.