Manchester - Jose Mourinho risked causing another rift with his Manchester United stars as he slammed his defence's lack of "technical quality" after their 0-0 draw with Valencia.
READ: Mourinho's Man United misfire once more
The frustrating Champions League clash at Old Trafford means Mourinho's side have gone four games without a win in all competitions.
United rarely looked like scoring against their out-of-form opponents and were booed off at full-time.
It was another blow for Mourinho, who has come under fire after presiding over United's worst since to a league season for 29 years.
Mourinho has feuded with star midfielder Paul Pogba, as well as other members of his squad.
And now he has taken a swipe at his back four, which against Valencia featured Antonio Valencia, Chris Smalling, Eric Bailly and Luke Shaw.
"We don't have the technical quality to build from the back," Mourinho said.
"The players tried. They raised the level of their intensity in spite of the fact we don't have many with that intensity.
"We had probably a couple of the biggest chances to win it but I have accepted the result as a fair result."
Mourinho admitted United had focused on stopping Valencia causing them problems, even though they were at home, because his team are so badly lacking confidence at present.
"We tried to do something we did well which was to stop a fast team on the counter attack. We knew we wouldn't create 20 chances," he said.
"Our attacking players aren't in their best moments of confidence and individual level. We thought with three or four chances we would score and win the game.
"It is a not a bad result. Not a good result, but not bad. We have two matches against Juventus to make points. It is a very difficult group, yes.
"We have Newcastle (this weekend) before the league stops, then we have Chelsea and Juventus in three days. It will be good for the team if we can beat Newcastle."
Belgian attacker Romelu Lukaku was singled out for criticism after putting in an unconvincing display that was summed up when he left the ball behind when trying to take on a Valencia defender.
Lukaku was soon being ridiculed on Twitter and other social media platforms with some saying he managed to tackle or even nutmeg himself.