Lampard’s side have been beaten three times by United already this season.
Chelsea were thrashed 4-0 at Old Trafford in Lampard’s first Premier League game in charge.
They also suffered a 2-1 loss to United in the League Cup fourth round, while Ole Gunnar Solskjaer’s team extended their dominant run against the Blues with a 2-0 league victory at Stamford Bridge in February.
Lampard conceded United were largely the better team on those occasions and the Chelsea manager is focused only on getting his side set up right this time.
“Knowing the circumstances of the games, fair play we’ve lost three, that’s just a fact, and I’m not into revenge, I just want to win the game in front of us on Sunday,” Lampard told reporters on Friday.
“We played some good stuff in the Carabao Cup. We played a very changed team and played some good stuff, but you still lose.
“And in the league we had a good first half, missed opportunities and they took theirs.
“So I think you have to respect the fact that they’re a good team, we can all see that in their recent performances, but I’m not overly concerned with the games that have gone by. I just want to win the one in front of us.”
United have seen a host of VAR decisions go in their favour recently, including two key calls in their league win at Crystal Palace on Thursday.
Wilfried Zaha was denied a penalty just moments before Marcus Rashford put United ahead, with Jordan Ayew also seeing a goal ruled out for offside.
Lampard, whose side are battling United for a top-four finish in the league, admitted the VAR decisions have given a helping hand to their rivals during their recent run.
“There is always a human element to VAR still, of course. Clearly they have to make a decision,” Lampard said.
“The confusing thing about some of the recent decisions and the one last night (Thursday) is that it’s a very clear and obvious decision that is wrong, that didn’t get reviewed and changed.
“And a few of those have happened. And that is strange.
“I would like to think sometimes you have to be level-headed. Some may go against you or not, but it just seems a period where Manchester United have got a few in their favour with VAR.”