Sean Dyche was left to mull over another defensive mistake that hand Manchester United the upper hand in a tight Turf Moor affair.
Charlie Taylor conceded possession a minute before half time to allow the Reds to pounce through Anthony Martial’s crucial opener.
Thart came after a simiilar error from Dwight McNeil at Everton 48 hours earlier, which handed the Toffees the points.
And despite a spirited second half that gave United’s young side a stern test of their credentials, Marcus Rashford’s stoppage time second consigned the Clarets to back-to-back festive defeats.
Burnley boss Dyche said: “The mistake has a big part to give them a head start, for sure.
“In the first half they had a good foothold in the game, without opening us up too much, and I was quite pleased with that aspect of it.
“It’s hard to contain these sides, as a starting point, but we looked to build into the game and the mistake changed the feel.
“In the second half I was super pleased. The reaction as good and we took the game on.
“We needed that goal, obviously, to see what that could then generate. but we couldn’t get that breakthrough.
“We did ask questions and mixed our play better and the mentality was good, as was the level of fitness.”
Dyche, whose side end the calendar year in 13th place in the Premier League, added: “I was very pleased with Dwight McNeil again, but there weas a lot to be pleased about tonight and if we’d just got that goal to equalise, you never know.
“Phil (Bardsley) forces a good save from De Gea, and Dwight gets in a good position in the first half and doesn’t strike is as cleanly as he can.
“Barnesy had a chance in the first half and Dwight had another in the second, so we are creating chances again.
“There were some good details in the game and I am pleased with that side of it, but you have to be clinical and that was the key to it tonight.
“The thing for me is getting back to the performance levels.
“We’ve ground a few out and we nearly ground one out at Everyone, other than a mistake.
“But we don’t want to keep grinding every week. It’s important we can do that, but our play was better tonight and I was pleased that we were more productive.”