At the Australian Open, Bianca Andreescu Is the Great Unknown

Bianca Andreescu of Canada won her first match in 15 months, a three-set nail-biter against Romania's Mihaela Buzarnescu at the Australian Open on Monday.Credit...Paul Crock/Agence France-Presse — Getty ImagesMELBOURNE, Australia — As Bianca Andreescu vaulted from No. 152 in the world to the United States Open champion during 2019, she appeared to be playing with a tennis angel on her shoulder.

And then good fortune left Andreescu, the 20-year-old Canadian, shortly after she lifted that U.S. Open trophy.

Andreescu sustained a torn meniscus that October. Then came the coronavirus pandemic, which, combined with the knee injury, kept her from competing for all of 2020. She trained through the…