American qualifier Jamie Hampton upset 2009 champion Caroline Wozniacki 6-7 (8), 7-5, 6-3 to reach the Eastbourne final on Friday.
Hampton will play the first final of her career against Yanina Wickmayer or Elena Vesnina. She'll attempt to become the first American woman to win the title since Chanda Rubin beat Conchita Martinez in 2003.
The 41st-ranked Hampton's victory came after she lost five set points for the first set. The ninth-ranked Wozniacki also served for the match at 5-4 in the second, but failed to convert.