In the run-up to last Sunday's Premier League match between Liverpool and Manchester City, Jurgen Klopp compared the ongoing competition between the two clubs to another famous rivalry.
"I think Nadal and Federer enjoyed the rivalry they had," the Liverpool manager said. "That's how it is in sport. I wouldn't say I'm thankful City is that good, but it didn't harm our development."
Tennis doesn't allow for draws like soccer, of course, but the fact that three of the teams' last four meetings resulted in a tied scoreline certainly hints at the evenness of the rivalry.