New signings at Liverpool and United and will be forewarned by team-mates and staff to expect a game different to anything else they will experience during the season, but you have to live it to understand it. Time and again we see how often the challenge is too much for those playing at Old Trafford or Anfield for the first time in an away shirt.
Across the entirety of the 1980s, when Liverpool were for a long time the best side in Europe and finished outside of the top two just once, they enjoyed a solitary league victory at Old Trafford. They won there only once in the 1990s, too.
Those two wins in 20 years made me especially proud to be part of a side that reversed that trend in the early 2000s when we won three times at Old Trafford in four seasons. But that was an anomaly. There have been 12 Liverpool defeats and five league wins at Old Trafford in the past 20 years.
On the surface that looks like a poor run. Actually, a 25 per cent win rate at the home of your great rivals is a reasonable return, reflecting how tough it is to go there.
It is one of those stadiums where you feel the weight of history as soon as the game kicks off, sense a different vibe trying to get through the 90 minutes, and never feel comfortable, no matter what the score.
Usually the Anfield fixture is hyped up for the atmosphere, as though it is more difficult for United players going there than the other way around. I can assure you it works both ways.