WATCH: The story behind Jamie Carragher’s vicious Twitter takedown of Didi Hamann

Wow. That escalated quickly.

It started off with Dietmar Hamann calling out his former Liverpool team-mate Jamie Carragher for telling current Reds keeper Loris Karius to "shut up" during his analysis of the match on Sunday. Karius was under fire for the second match in succession after Liverpool conceded twice against West Ham, with questions again asked about the German stopper's role in both. On Match of the Day 2, former Manchester United and Everton man Phil Neville criticised Karius for hitting back at the critics in a newspaper interview that ran last week. Hamann was not impressed with Neville's stance and tweeted: https://twitter.com/DietmarHamann/status/808264049469358080 A fan pointed out that Carragher had already said exactly the same thing during Sky Sports' live coverage of the match - something another Twitter user was quick to point out. And clearly their shared Liverpool history was not reason for Hamann not to disagree with his former team-mate. https://twitter.com/DietmarHamann/status/808267648840728576 https://twitter.com/DietmarHamann/status/808269076506279936 Carragher's response was genius - if a little predictable. https://twitter.com/Carra23/status/808291367139115008 https://twitter.com/DietmarHamann/status/808291521820786688 But it was this mysterious retort from Carragher that really upped the ante in this particular Twitter spat: https://twitter.com/Carra23/status/808293510407405569 Now, with a little bit of detective work (or Googling. Whatevs), we found this video, which seems to explain everything vis-a-vis "Tokyo 2005" - and is well worth six of your minutes... https://youtu.be/hJXfnJBbSas