It would be a familiar sight at Chelsea's training site in Cobham.
Swedish club captain and centre back Magdalena Eriksson battling it out with Australian national team captain and striker Sam Kerr.
In a full season together at Chelsea the pair have worked against each other in training sessions before doing their respective jobs at opposite ends of the pitch for the same cause.
And it's been highly successful for the Blues. In the 2020-21 FA WSL season, Chelsea won its second consecutive league title. Kerr claimed the golden boot with 21 goals in 22 appearances. Eriksson led from the back.
The team also won the Conti Cup with a strong 6-0 win over Bristol, Kerr scored three of the goals, and made it all the way to the UEFA Women's Champions League final.
But on Saturday in Saitama Stadium, Kerr and Eriksson will be on opposite teams - and both will want the win.
The Matildas taking on Sweden is highly anticipated. The Swedes' 3-0 victory over the USA was a statement of intent, while Australia sits in second after a 2-1 win over New Zealand.
The match will grant the winner almost certain progression to the knockout stages of Tokyo 2020.
But the clash is intriguing in other ways. The pair played out a scoreless draw in a friendly in June with both sides keeping some of their cards close to their chest.
ULTIMATE GUIDE: Sweden v Australia Tokyo 2020
It would have also been the first time fans saw Eriksson and Kerr do battle as adversaries rather than teammates but the Swedish defender was subbed early for precautionary reasons.
After missing the game against the USA, Eriksson has declared herself fit and ready to play. Meanwhile, Kerr ended a five-game goalless streak against the Football Ferns and set up the other Aussie goal.
After the Olympics Kerr and Eriksson will return to Cobham and work to help Chelsea win more trophies and try and go one better in Europe. But on Saturday, their battle within the battle will be one to watch.