Jose Mourinho's time as Real Madrid manager came to an end in the summer of 2013.

Following a tumultuous third season in charge of the Spanish side, the Portuguese manager and Los Blancos parted ways in a mutual agreement.

Mourinho then re-joined Chelsea and that meant he would come face-to-face with his former employers in pre-season.

The two European giants were to meet in the final of the 2013 International Champions Cup and five days before the game, the Portuguese decided to up the ante by taking a swipe at Cristiano Ronaldo.

"I was manager for the first time in the 2000 year but, before that, I was assistant in big clubs and with big managers and coaching the best players in the world, so I was 30 and I was coaching Ronaldo, not this one [Cristiano], the real one, the Brazilian Ronaldo," Mourinho told ESPN, per Goal.

Ouch. Ronaldo and Mourinho didn't exactly see eye-to-eye during the latter's time as manager of Real Madrid.

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According to Guillem Balague, the pair once came to blows in the dressing room in 2013 after a disagreement in a win over Valencia.

There was real animosity between the pair and the sly dig from Mourinho in the build-up to the International Champions Cup final must have seriously got under Ronaldo's skin.

But in typical fashion, Ronaldo done his talking on the pitch, producing an absolute masterclass in the game to secure a 3-1 win for Real Madrid.

The five-time Ballon d'Or winner scored a stunning free-kick to put the Spanish side 2-1 up in the first half, before netting a brilliant header after the interval to finish off Chelsea for good.

Take a look at Ronaldo's stunning highlights from the day he got sweet revenge on Mourinho:

That's Ronaldo at his very best.

His free-kick at 3:50 in the video was absolute perfection and there was no chance whatsoever that Petr Cech in the Chelsea goal was saving it.

Ronaldo's towering header wasn't bad either and it capped off a performance that should serve as a constant reminder to the fact that it's wise not to make the 36-year-old superstar angry.