American player Venus Williams rallied from a set down to beat Serbian Ana Ivanovic 4-6, 6-3, 6-4 on Saturday in the Zurich Open semi finals.
Williams will face Flavia Pennetta in Sunday's final, after the Italian beat Spain's Anabel Medina Garrigues 6-3, 7-6 (6) in an earlier match.
Pennetta holds a 3-1 career record against the 28-year-old American - the older Williams sister - and beat her in Moscow last week.
The third-seeded Williams is looking for her second singles title of the year, after winning Wimbledon, as she tries to secure a place in the season-ending WTA Tour championship in Doha, Qatar, next month.
Williams is also a defending Zurich Open champion, having won the tournament in 1999. It will be her last chance – the Zurich Open WTA tour event is ending in 2008 after 25 years.