Manchester - Ole Gunnar Solskjaer admitted on Saturday that Manchester United will have to improve significantly on their performance against West Ham if they are to knock Barcelona out of the Champions League.
A much-changed United were unconvincing as they beat Manuel Pellegrini's side 2-1 at Old Trafford to maintain their hopes of a Premier League top-four finish thanks to two Paul Pogba penalties, three days before they try to overturn a 1-0 first-leg deficit in their Champions League quarter-final decider at the Camp Nou.
"We were lucky it wasn't Barcelona today," said Solskjaer.
"They played better than us but we have one of the best goalkeepers in the world."
Felipe Anderson, who had earlier had a goal dubiously disallowed for offside, scored early in the second half to make it 1-1 and Michail Antonio went close twice, hitting the bar and watching in disbelief as David de Gea pulled off a wonder save on his header seconds before Pogba's second spot-kick won the game 10 minutes from time.
"That save is unbelievable. He won us the game because at 2-1 down, we would have struggled to create enough," added Solskjaer.
"We sit here with three points and we got the points. We were fortunate. I can't hide that."
Solskjaer made five changes to the team that lost to Barca on Wednesday, leaving the rested Marcus Rashford, Scott McTominay and Victor Lindelof on the bench, while Luke Shaw and Ashley Young were suspended.
"We had Rashford, McTominay, and Luke Shaw out, and there is intensity and power in those players," added Solskjaer.
"It was end-to-end like a basketball game at times. I think the intensity was not bad, if you look at the physical stats - but the control was not good enough."
Solskjaer was unhappy at the six-day turnaround between United's two legs against Barcelona, while there are eight days between Manchester City, Tottenham and Liverpool's quarter-final ties.
"Someone needs to explain to me why in the Champions League it is Wednesday and Tuesday matches for us and Tuesday and Wednesday for the others," he added.
"We tried to Google it but didn't find anything. UEFA should change that 100 percent."
Those Champions League ties will have VAR on hand for controversial calls and West Ham manager Manuel Pellegrini believes the Hammers would have won had the technology been available to referee Graham Scott on Saturday.
"With VAR, I am sure we would win the game 1-0. Felipe Anderson was onside. It was not a penalty from Robert (Snodgrass).
"The last goal from Manchester United was offside, the last pass. There were a few mistakes but the decisions went for United.
"I am not complaining about the referee because they were not big mistakes, they were 'difficult' mistakes but with technology we have a different score."