He returned to Spurs and appeared set to be a member of the first-team squad rather than go on out on loan for the upcoming season despite interest from top-flight and Championship clubs.
The England Under-21 global is one of the best and most promising young players in England, and it may have come as a surprise to Tottenham fans when it was announced that the midfielder was leaving on loan for a club in the Championship.
Speaking ahead of Villa's season opener at home to Hull City on Saturday, the Englishman spoke of his determination to hit the ground running and impress manager Steve Bruce.
'This is a huge football club and I want to really make my mark here and prove to be a player the manager can rely on.
The Enfield-born midfielder may have designs on breaking into Pochettino's starting line-up in the future but is now exclusively focusing on helping Aston Villa earn promotion back to England's top-flight.
Onomah is now the 12th player to leave Tottenham this summer. Pau Lopez has meanwhile returned to Espanyol after failing to win a permanent deal following his loan spell.
Aston Villa fans: What do you think Josh Onomah will bring to your side?
So, where will Onomah fit in at Villa?