Lisandro Martinez says he can “see a light” at Manchester United despite Sunday’s “unacceptable” 3-0 home defeat to Bournemouth adding to the darkness around the club.

The Red Devils were booed by some of their own fans as they suffered a humiliating Old Trafford loss to the Cherries just a week after a memorable late derby win at Manchester City.

United lacked that spirit and cutting edge when Bournemouth visited, with Dean Huijsen becoming the latest player to exploit their set piece fragility when nodding home a first-half free-kick.

Amorim acknowledged the need to address that weakness, so too his players’ inability to deal with setbacks after Antoine Semenyo scored two minutes after Justin Kluivert converted a penalty.

Bournemouth left Old Trafford with a 3-0 victory – just as they did last December – but defender Martinez believes things are on the up despite the club heading into Christmas languishing 13th.

“We are very disappointed because I think we are playing so well,” the Argentina international said. “We are playing so well, we create many chances and unfortunately we couldn’t score, so disappointed.

“We have to adjust a few things, especially at set pieces, but I think we have to start games scoring the first goal. We want to work on that.

“I think we have a great coach and a great group as well. We have the chance now because we know in this club losing is unacceptable, but we are here to change things.”

Put to Martinez that United do not appear to be getting rewarded for improving performances, he told MUTV: “Yeah, for sure we deserve more. I see a light in this club that I think we are going to achieve that.

“You see in the games that we are improving. We have to believe and for sure it’s hard to accept this kind of result.

“But I believe a lot in the staff, in our team and, how I said, we are going to change this.”

The Bournemouth defeat came hot on the heels of Thursday’s chaotic 4-3 Carabao Cup quarter-final loss at Tottenham – a double blow United will look to bounce back from at Wolves on Boxing Day.

“We have to now recover and then prepare well for the game because we need points,” Martinez added. “We want to change this situation. I am 100 per cent confident on that.”

As United nurse their wounds, high-flying Bournemouth sit fifth in the standings at Christmas – a place that could prove enough to seal Champions League qualification come the end of the season.

Andoni Iraola’s impressive Cherries will look to extend their unbeaten run to six and collect a fifth victory when Crystal Palace come to town on Boxing Day.

“Shellshocked, to be honest,” goalscorer Semenyo said. “It’s back-to-back wins here.

“I think we got the press right. I think everything in the first half and the second half we done (sic) it to a tee and, yeah, it’s just a good team performance.

“3-0 away, three points. It’s lovely. It’s just great.

“Definitely (we’re) in a good run of form. We just need to keep going, just have to be positive.

“Everyone’s buying into what the manager’s doing in training and you can see it in games as well.

“So, (we) just have to keep pushing and who knows what this team can do?”