There won't be another ASB Classic title for Venus Williams this year, but there may yet be one for Julia Goerges.
Defending champion Goerges moved one step closer to back-to-back Auckland titles after Friday's quarter-final matches.
The German world No 14 not only came from a set down, she saved a match point on her way to beating Canadian star Eugenie Bouchard 3-6 6-3 7-6 (6).
Seven-time grand slam champion Williams, however, was on the wrong end of a second straight upset win for Canadian teenager Bianca Andreescu.
A day after knocking out world No 3 Caroline Wozniacki of Denmark, 18-year-old Andreescu put on another stunning display to oust 2015 Auckland champion Williams.
Goerges' semi-final on Saturday will be against Viktoria Kuzmova after the world No 50 from Slovakia scored a 6-2 2-6 6-4 victory over American Amanda Anisimova in the opening quarter-final.
Andreescu will face Taiwan's Su-Wei Hsieh, who dispatched Sara Sorribes Tormo of Spain 6-3 6-2 in the last of the quarter-finals.
Whatever happens from here, though, the young Canadian has achieved a career milestone this week.
Saturday's match will be her first semifinal at a WTA tournament, a feat she has achieved in memorable fashion.
However after knocking out Wozniacki, repeating the dose against Williams became more difficult when the 38-year-old American took out their first set tiebreak.
Andreescu didn't relent with her attacking style, though, and it suddenly started to pay off as she raced away to take the second set 6-1.
The one-way traffic continued in the third, as the young gun raced out to a 5-0 lead.
A few nerves did creep in as Williams rattled off three straight games to threaten a miraculous comeback, but Andreescu settled enough to seal her spot in the final four.
Goerges win over Bouchard came in blustery afternoon conditions.
With the stiff summer breeze that had blown throughout the Kuzmova-Anisimova match persisting, it was Bouchard who was quickest to make the necessary adjustments.
The former world No 5 and Wimbledon finalist, who has risen back to 87th in the rankings after struggles with injury and form, got her nose in front and secured the first set.
However Goerges made the most of her fresh start, fighting hard for a break of serve before sending the contest to a decider.
There was little between the two players in the final set, where the quality of tennis was high considering the difficult conditions.
But, having saved a match point at 5-4 down with a clutch second serve, it was Goerges who prevailed in the tiebreaker, eventually securing a semifinal berth on her third match point.