Kerber made home advantage count, following up a 2-6 6-3 6-3 quarter-final win over Amanda Anisimova – a match that was pushed back from Thursday when rain washed out play – with a triumph over top seed Petra Kvitova.
The former world number one came back from behind to win 3-6 6-4 7-6 (7-3) and take a spot in her first WTA singles final since 2019.
Kerber and Kvitova have now met 15 times, with the German winning on nine occasions.
She will go up against an unexpected finalist in the form of Siniakova, who defeated Sara Sorribes Tormo.
The Czech is the world number two in doubles, winning three grand slam titles in that format, and will be looking to replicate the feat of her regular partner Barbora Krejcikova, who triumphed at the French Open this year.
A beautiful week doesn’t always end with the trophy. Thanks @badhomburgopen for putting on a fantastic event.
Next stop? @Wimbledon pic.twitter.com/XnQHfU9BZZ
— Petra Kvitova (@Petra_Kvitova) June 25, 2021
At the Viking International in Eastbourne, Jelena Ostapenko made light work of Elena Rybakina, while Anett Kontaveit made it into the final due to Camila Giorgi’s retirement.
Latvian wildcard Ostapenko finished her 6-4 6-1 victory with zero double faults – the first time she has managed such a performance since winning in Luxembourg two years ago.
“I’m really happy with the way I played this week, and every match I played better and better,” Ostapenko told a news conference after clinching a spot in her ninth career final.
“It’s been a while [since making a] final, so I’m really happy to be in a final and looking forward to tomorrow’s match.”
The 2017 French Open champion will face Estonia’s Kontaveit, who has won their previous two meetings and was 5-4 up in the opening set against Giorgi when her opponent retired hurt.
“It’s actually nice to have a Baltic final, because [we’re] not such big countries, but we still have good players,” Ostapenko added.
“Anett, I know since juniors. We have been playing a lot, maybe not so many matches but we practice sometimes together, in juniors, and played even doubles. So I know her quite well.”
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