"My perception is he arrived Monday, happy, proud, with a desire to work", Mourinho said ahead of Friday's opening Premier League fixture against Leicester.
It is understood United officials have grown increasingly tired and suspicious of Pogba's high-profile agent Mino Raiola, whom they blame for stories that his client would prefer to play for Barcelona.
Following a successful summer in which he helped France to win the World Cup, Pogba's future at United has been the subject of speculation over the last week of the Premier League transfer window.
Looking at the year as a whole, the club has brought in Alexis Sanchez, Brazilian midfielder Fred, promising full-back Diogo Dalot and a veteran goalkeeper, in Lee Grant, that looks set to deputise for David De Gea this season.
"This is Man United", said Merson.
After the finals it was not the price being quoted for Mina but the structure of the agents' fees being proposed that made the Old Trafford club uncomfortable.More news: Newcastle sign Japan's Yoshinori Muto, as Rafa Benitez expresses concerns
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In the United Kingdom, the game will air on BT Sport Live. Bayern Munich defender Jerome Boateng is Mourinho's first choice, but has reportedly phoned the Portuguese coach to tell him he won't be joining. His loan spell at Crystal Palace seemed like a sensible option but he found his football hard to come by with the management changes at Palace; it was hoped that he would be in contention for United this summer, as he surely has the quality to make an impression in that area.
United contacted Atletico Madrid about Diego Godin but it quickly became evident that the move was a no-go, while an official offer was not made for Tottenham's Toby Alderweireld.
How Mourinho reacts from now will be dictated to some extent by results, but the key objectives at the turn of the year have all been fulfilled as far as the club are concerned. But I am astonished, astonished that a club of their ilk, a club with their clout, a club that were so far off the pace past year in terms of the points gap, that they have done little or nothing.
Internally, the greatest frustration for Mourinho has been waiting for the return of those players who had the longest World Cup campaigns.
"But it's the same conversation as with (Ashley) Young, (Marouane) Fellaini, (Jesse) Lingard, it's the same".
Jose Mourinho confirmed that as many as 10 players are likely to miss the Premier League opener.