Brydan Klein has failed in his bid to reach the final of the Aegon Surbiton Trophy after losing out to Denis Kudla.
The British number six has impressed during the opening two weeks of the grass-court season, but a break of serve in each set was enough for his American opponent to run out a 6-4 6-4 winner.
Ireland's James McGee also missed out on his chance to progress past the last-four stage after being comfortably beaten by Matthew Ebden.
Ebden, who has reached as high as 61 in the world rankings, eased to a 6-2 6-3 victory.
