He believes Chelsea's attacking approach is one reason for their good record. "Traditionally, Old Trafford has been a happy hunting ground for Chelsea," he said.
"I don't know why, but it could be that Chelsea have always had a good attack. Also, everyone raises their game for matches at Old Trafford because it's a bit like going to Wembley. It lifts players and makes them more determined to excel," Sexton said.
"I think Chelsea, despite all their ups and downs, have always had the type of players who relish the opportunity of playing on a great stage."
Sexton's most memorable Old Trafford win came in August 1968 when Chelsea overwhelmed the then European champions. "They had George Best and the rest of them playing, but we won 4-0," he said.
Chelsea are emerging as genuine title contenders and have not lost in the Premiership since the opening day of the season - to Coventry.
Sexton is impressed by how their manager, Gianluca Vialli, has carried on the work of Ruud Gullit, now with Newcastle. He believes they have finally found the right consistency.
"If you are going to do well in the League you have to be consistent, and Chelsea have found that. They have silenced a few of their critics with this long unbeaten run.
"What they need to do now is to win more games and to keep scoring regularly if they want to be serious about winning. Despite their record at Old Trafford, though, it will still be very daunting for them."