Rio Ferdinand may have hung his boots up at the end of the 2014/15 season but he still likes to keep himself in shape.
Not only that, he also likes to show everyone how he stays fit by posting regular updates of his various exercise routines on Instagram.
And he updated his 1.7 million followers with another video of an exercise from his latest workout on Monday.
The clip showed the 37-year-old on all fours performing a 'bear crawl' with a dumbbell in each hand.
All sounds fairly normal at this stage, right?
Well, what Ferdinand wasn't expecting was to be on the receiving end of a sly dig from one of his old teammates - none other than Cristiano Ronaldo.
As well as exercising, the ex-England defender also spends a lot of time working as a pundit and is regularly providing his opinion on BT Sport.
As a pundit, Ferdinand is all too familiar with taking some stick but couldn't resist biting back when another former Red Devil commented on his unusual workout.
You can see the brief conversation below as Ronaldo simply wrote: "Wtf is that??????"
Ferdinand responded by trying to advise Ronaldo to start performing the same exercise but it was too little too late - the Real Madrid star had already won this exchange.
The pair spent six years at Old Trafford together before the Portuguese forward signed for Real Madrid in 2009.
Despite moving to Spain, Ronaldo is still highly regarded by Red Devils supporters so as you would expect, it sent many fans into hysterics to see their former idol mock Ferdinand.