The visitors raced into a 3-0 lead within 28 minutes thanks to two goals from Jay Rodriguez and one from Rickie Lambert.
All the talk before the game was about Mackay's future, but speaking to Sky Sports after the game, the Scot refused to use his own uncertainty as an excuse.
Mackay said: "I can't make excuses for that. My team have been working hard but we made three errors.
"I haven't been given a date yet or know when I will meet the owner but I will be in training tomorrow and if it was down to me I will still be in charge against Sunderland.
"I have great players and a great staff here and we are in the Premier League so we should be enjoying it. It's not easy when some of our laundry has been aired in public."
Overall Mackay said that he has been pleased with how his team have adapted to Premier League life and he thanked the home support for their help.
Mackay added: "Overall we have competed in the Premier League really well. It is easier when everyone is pulling in the same direction.
"The fans have been great but I think they realise how hard me and my staff have been working here."