According to him, this is because it will be David Moyes seated in the visiting dugout.
Prior to succeeding Sir Alex Ferguson as United boss this summer, Moyes was in charge of Liverpool's Merseyside rivals Everton for just over a decade.
Johnson told www.liverpoolfc.com: "A lot of families in this city are split - some are Red, some are Blue.
"I'm sure the Liverpool fans will still see him as part of Everton so I'm sure to those families it will add a little more spice."
Moyes, under whom United have so far beaten Wigan in the Community Shield and then won at Swansea and drawn at home against Chelsea in the league, never led Everton to victory at Anfield during his 11 years with the Toffees.
The Scot will no doubt be keen to take all three points from Sunday's game, while Johnson has emphasised that the same very much applies to Liverpool.
Brendan Rodgers' side have a 100 per cent record to date this season, having won at home against Stoke and away against Aston Villa in the league and secured an extra-time home victory over Notts County in the Capital One Cup second round on Tuesday.
And regarding the targets for Sunday and the rest of the campaign, Johnson said: "Obviously the objective for this weekend is to win.
"We've started well and we want to keep the run going.
"It's the last game before the international break so it would be good to finish that period with three (league) wins.
"Like I've been saying for many years, the target is to get into the top four - that is our objective, it's what the club wants and needs.
"That will definitely be the aim. We just take each game as it comes and hopefully we'll be there or thereabouts."
The 29-year-old England full-back is relishing the prospect of the atmosphere Anfield is set to provide on Sunday for a fixture he has no doubt remains one of the great football occasions.
Asked about the noise level from the stands at Liverpool-United matches, Johnson said: "It's what you want.
"It's fantastic to hear and they are the games you want to play in. When the crowd are with you they give you that extra yard and make you want to fight even harder.
"I don't think anybody outside of the two clubs or two cities realises how fierce the rivalry is.
"It's great for the game and great for the Premier League as well.
"This is the one game that any outsider would tune in to watch."
Liverpool centre-back Martin Skrtel is set to make his return to action in Sunday's contest.
Skrtel, yet to feature this season, is available after recovering from a knee problem but full-back Aly Cissokho will play no part in the game after picking up an ankle injury against Notts County that Rodgers says could see him sidelined for ''four to six weeks''.
Two other Liverpool players who came off injured in that match, defender Kolo Toure (groin) and midfielder Joe Allen (hamstring), are both doubts.
Striker Luis Suarez misses out again, although he could face United at Old Trafford in the Capital One Cup third round next month as his 10-game suspension will then have been completed.