The United captain played Matheus Cunha through for the only goal of the game, with three points moving the Red Devils within striking distance of a Champions League place with five matches remaining.
Fernandes needs just two more assists to equal the record of 20, set by Henry for Arsenal in 2002-03 and De Bruyne for Manchester City in 2019-20. Mesut Özil is the only other player to have reached 19, with United's captain now sitting ahead of Mohamed Salah, Cesc Fàbregas, Frank Lampard and De Bruyne's 2016-17 tally.
The 31-year-old has scored eight goals alongside his assists this season, delivering one of the most productive individual campaigns the Premier League has seen from a central midfielder. He was measured in his reaction after the game, insisting the focus remains on the team's European ambitions rather than personal milestones.
"We are three points closer to Champions League now. We have to get the points as quickly as possible, and we will do everything to get them," he told BBC.
“It’s an amazing feeling for us. We had to bounce back - it’s not just about Leeds, there were two games that we didn’t win.
“But we knew we had to make a great performance today because Chelsea are a very good side and it was very important for us because we know our aim is to get in the top four and they are the closest one to the top five. Making distance is important for us and that’s what we need.”
Chelsea's 1-0 defeat left them sixth and four points outside the top five, their Premier League goalless run stretching to 386 minutes. Five games remain for both clubs.