Hernandez is now likely to make his Premier League debut for the Hammers against his former club and said of the Red Devils ahead of the game, "It was a great experience [there] ... only happiness".
"He was very clear, by showing what he did a year ago, that it was not enough for him", Mourinho told reporters on Friday.
He has trained with the club during his rehabilitation, though, and Mourinho has made clear he still believes the forward can do a job for him.
"We have had a better pre-season than previous year and we have the confidence levels of a team that has won a European competition and returned to the Champions League".
Mourinho has indicated that he wants a fourth signing before the transfer window shuts on August 31, as he needs a winger to bolster his squad.
Mourinho reiterated at a pre-match conference yesterday his satisfaction with the club's transfer business this summer window, despite not achieving "100 per cent" of his targets.
"It's not urgent, not desperate to have it done or not done", said Mourinho.
"He wants more football at the highest level so we are having conversations and discussing the possibility of him staying for the second part of the season".
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However, Guam's security agency has issued a fact sheet with advice on what residents should do in the event of a nuclear attack. We've got 95 per cent occupancy and after all this stuff comes down we're going to have 110 per cent occupancy".
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The administration official who confirmed that Trump would sign the order contended it was unrelated to the showdown with North Korea.
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It is no wonder that Liverpool want "The Little Magician" to remain with the club as has really flourished at Merseyside. The statement said: "Philippe has tried very hard to find an amicable solution to this situation but to no avail".
Ahead of the Premier League opener against West Ham at Old Trafford on Sunday, he said: "My initial analysis from January and progressing through other months I was thinking of four players but I am not a hard person to work with, even if looks different or you want to make it look so".
However, Mourinho has lost a number of key players to long-term injury, including defenders Marcos Rojo and Luke Shaw, and wing-back Ashley Young.
"There are obviously bigger competitions than others, but we will certainly be fighting on all fronts to win as much as we can".
"I think everybody is in Europe".
Mourinho says he is after another player "coming from the sides" to complete his summer business - leaving the door open for either a winger or a full-back.
"I'm happy with the club's efforts". I'll just go with everything I have to try to win every match we play. "He's not got a contract, but he's still close to Manchester, and the fact we are involved in the Super Cup now is also his merit".
"It's the way I trust the player is going to perform so I think it's a fantastic signing for us".
"So between the players we lost and the players we got, I think we are in a similar situation".