The on-pitch rivalry between Jamie Carragher and Gary Neville was infamous back in the defensive duo's playing days.
Both one-club-men on either side of one of English football's greatest rivalries, coming out of football it was hardly likely a Liverpool legend and Manchester United legend would become best of friends.
However, since hanging up their boots, Carragher and Neville have successfully worked together on Sky Sports, setting aside their differences to produce some incredibly entertaining sports broadcasting.
Though it seems the change of scenery has brought about a shift in the Carragher-Neville rivalry, as nowadays the two resort to light-hearted jibes via social media.
If you follow either of the duo on Twitter you're likely to see the two engaging with one another, sometimes taking part in a constructive dialogue, sometimes not.
Monday night was an instance where the lingering embers of their rivalry flared up once more, with Carragher making a light-hearted joke about Neville's dress-sense.
After being picture alongside David Beckham, Neville was on the receiving end of some scathing comments from Carragher, as the former Liverpool man tweeted: "WTF! The return of the Fonz! You're only from Bury!! @GQMagazine get a load of this killer!!!!"
While the Liverpool legend may be ahead of the Manchester United man in this Twitter war, the real-life football landscape could not be any more different.
Manchester United are currently joint first in the league with local rivals, Manchester City, whereas Liverpool sit in seventh, seven points behind the Red Devils.
And with the two set to face off against one another at Anfield after the international break, it may be well worth keeping an eye on the social media activity of Carragher and Neville in the build-up to the big match.