Bastian Schweinsteiger is a burly, German international who deals with rash challenges in midfield on a weekly basis, but even that doesn't compare to his girlfriend's tough personality.

Ana Ivanovic defeated Kateryna Kozlova in the quarterfinals of the St. Petersburg Ladies Trophy on Friday, 6-1, 7-5. The victory sees the No. 2 seed advance to the semifinals, where she'll meet Roberta Vinci.

Ivanovic, Schweinsteiger Benefitting From Time Apart

But that's not where we're going with Ivanovic's narrative. Instead, it dates back to her training as an amatuer.

You know, when she would train in between bombings in Serbia.

Ana Ivanovic In Better Shape Than Her Boyfriend

"When the bombing was happening, from about noon to about 6 a.m., we had these sirens that indicated the danger of attacks, basically. So we would train from 7-9 a.m. then go back home and stay home most of the day," Ivanovic said, per Sportsnet. "But after a few months, they started to try to run everything like normal, so we had tournaments. Between bombings, we used to play tournaments and compete.

"The matches would start, and if the sirens came on, the matches would end and no new ones would start. Looking back, it was so silly to try to force that, especially because we were all kids. But it was our way of surviving too."

And you thought trying to take the ball away from David Silva was a tough ask.

Should Ivanovic advance to the finals, it will be her first since reaching the final of the Brisbane International in 2015.

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