A brace for Mohamed Salah, along with goals for Luis Diaz and Sadio Mane saw a hugely disappointing result for Ralf Rangnick’s side.
“It’s a bad result once again,” Bruno told Sky Sports. “Not much that I can say. Obviously, [we] apologise to the fans. It will never be enough but obviously it is what we can do now.
“They [the fans] don’t deserve that we play in this way, they deserve much more from us. The way they support us until the end, the way they stay even after the whistle to applaud us, they deserve much more from us.”
On the squad’s feeling on the result, the Portuguese added: “We have to say the things, but that has to be kept in the dressing room.
“We know there is not much we can do now the game is over. We have to think already to the next one that will be a tough one again.
“We have to look in ourselves, we have to look inside, from the top until the bottom and understand what is going wrong.”
Despite the difficult score-line, Bruno believes there is plenty still to fight for between now and the end of the season.
He said: “We represent a big club, we are competing till the end and we have to compete.
“No one can put their head down now and think that I just want to have vacations or whatever.
“They have to all of us have to understand that we have something to fight at least for the badge.”
Asked about the effort of the players, Bruno said: “I think everyone runs, I think every game is effort from everyone. I don’t want to think even that someone doesn’t give 100 per cent for themselves.
“Even for themselves and for the team. Everyone has to do it. In first place as I said for ourselves, after for the team and after obviously for the club we represent, the fans and everyone.”
Credit: Manchester United
