Sean Dyche revealed Jose Mourinho entered the Burnley dressing room and congratulated them on a hard-earned point, despite the Manchester United suffering a frustrating afternoon at Old Trafford.
United's frustration boiled over as Mourinho was sent to the stand at half time for his angry reaction to United not being awarded a penalty for a tackle on Matteo Darmian, while referee Mark Clattenberg also dismissed Herrera midway through the second half for two bookings.
Dyche told Burnley's official website: "I had no idea Jose had been sent off at half time. I only found out at the end of the game, but he came in and congratulated us, so fair play and I think his questions are not with us, but the referee today."
Burnley rarely threatened in the game and United had 37 shots on goal, but found Heaton in impenetrable form as he made 11 saves.
Dyche was full of praise for his England international goalkeeper.
"Tom was excellent and he knows he is going to have to be on top form," he said.
"But he is a very good goalkeeper and he continues to mature and work at his game and the biggest thing for me is he has that inner belief that goalkeepers need, that the ball is not going to go in the net.
"But I'm just really proud of the shape, the basics and doing all the ugly little things that count. Whatever the result today, there was more belief and that was a big thing and a building block.
"It isn't as easy as saying we can kick on because it's the Premier League and we know it's a tough task, home and away.
"But psychologically you come off the back of a real fight last week and a late goal, then to come here and fashion out a point was really important.
"The players get their shoulders back a little bit more now."