Manchester United manager José Mourinho has suggested his side's lack of intensity contributed to their 3-1 defeat to West Ham United at the London Stadium.
The defeat was the club's fourth in all competitions this season and equaled its worst ever start to a top-flight campaign in 29 years, having accumulated just seven points from ten matches.
The loss also condemned the Red Devils to a third consecutive match without victory, with the Portuguese insisting that his side didn't get off to the best of starts, following a draw against Wolves in the league and a penalty shootout defeat at home to Derby in the Carabao Cup.
Speaking to BT Sport, he said: “I think a team that comes with that mental fragility of the bad results, coming here and after five minutes is losing 1-0, is not the best way to start."
Felipe Anderson flicked home the opener from Pablo Zabaleta's low cross after just five minutes, but it appeared the Argentine was initially marginally offside and Mourinho indicated that it was an error from the linesman and had VAR been used, the goal wouldn't have stood.
He added: “A goal offside, a goal that last Tuesday with VAR, wouldn’t be a goal...That was obviously a linesman mistake and a goal."
Mourinho believed his side responded well after going behind and they went close to a leveler when Romelu Lukaku headed the ball against the post.
However, the former Chelsea manager was frustrated in the manner they conceded their second: "Then in the first-half, we had a good reaction. But an own-goal makes 2-0, an own-goal where we know that Yarmolenko is very, very, very left-footed, we know we have to cover that side.
"We had Matić on the ball, we had Luke Shaw and Lindelöf very close by, we are not aggressive and intense enough to close that shot and then we are losing 2-0 with an offside goal and an own-goal."
Mourinho opted to play three in defense and reverted midfielder Scott McTominay, to a center back for the game, a role that the youngster excelled in, according to his manager.
"He was the best, he had a fantastic attitude. He was aggressive, he was brave and had something that we thought was important for us, which is quality on the ball," he said.
"He knows how to play football, he’s technically good, he can bring the ball into offensive areas, so really happy with the job that he did."
Mourinho was also impressed by the center back partnership of the opposition's Fabián Balbuena and Issa Diop and praised the latter's dominant display.
"The center backs had a fantastic match. Congratulations to the scout that found 21-year-old kid Diop, a monster, who dominated everything in the duels."
Mourinho has been under pressure with his side's poor run of form and an alleged training-ground bust-up, following his decision to publicly strip Paul Pogba the vice-captaincy. The Portuguese has the opportunity to turn his side's fortunes around, however, with victories against Valencia in the Champions League and on Saturday against Newcastle.