What was Krejcikova's relationship with Jana Novotna?

It's one of the powerful images from the women's semi-finals of this 2024 edition of Wimbledon. The emotion of Barbora Krejcikova, who couldn't hold back her tears at the mention of Jana Novotna.
Novotna, Krejcikova's mentor
In 2014, when Krejcikova was 18 and ranked above 300th in the world, she learned that Novotna, former world No.1 and 1998 Wimbledon winner, lived in a village not far from her hometown of Brno. The young Czech then decided to ask her illustrious compatriot for advice on how to become a good professional tennis player.
Rise, then tragedy
The meeting between the two women went so well that Novotna offered to become her coach. She coached Krejcikova for two years, taking her to the doorstep of the WTA Top 100, before falling ill and dying of cancer in November 2017. She was only 49 at the time.