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."