Earlier in the day, Pochettino said: "At the moment we haven't received for any player".
Tottenham have become the first team in Premier League history not to make a summer signing since the transfer window's inception in 2003.
We didn't sell players and with 25 players in the squad it is hard to add players. "Building a new training ground, finishing this summer the (player's) lodge was a massive investment".
Grealish, who had been keen on testing his skills in the Champions League, is understood to be disappointed but will not try and force a move away from his boyhood club.
Deals for players like Danny Rose, Toby Alderweireld and Mousa Dembélé are yet to materialise however and Pochettino said he expected the players who remained at the club following the close of the window to knuckle down.
Mauricio Pochettino says the start of the season is a massive challenge for himself, as well as a number of other clubs.
The window remains open to European clubs until the end of August, so there is still the possibility of players going out even after the English deadline passes.
"It is better to keep our squad all together, we believe a lot in our players". Then you need to change your mind and think about the team and the collective.
"We didn't sell players and with 25 players in the squad it is hard to add players".
"It's true our targets are always the same level as Manchester United, Manchester City or Real Madrid but for different circumstances we can't achieve that".
"I am so happy in the way they come back to training on Monday".
"I am not anxious, I am not sad, I am so happy".
'We keep the best players. It told us we could not expect players to be signed or wages to be competitive while we opposed those ticket price rises. "Drama is many things in life but football is joy".