The 24-year-old midfielder was confirmed as Cobblers’ first summer signing on Friday after his impressive performances for the Mariners last season. Fox was offered a new deal by Grimsby and other clubs were also keeping tabs on his progress before Jon Brady made his move.
Asked what drew him to Northampton, Fox explained: "I think it was just the size of the club and the way the season played out last year and also the manager and the staff that are at the club.
"When I spoke with the manager last week, it just felt right. The club seems to be forward-thinking and heading in the right direction. Everyone wants to get promoted and that's the goal for me as well. This was an opportunity that I couldn't turn down.”
Elaborating on those conversations with Brady, Fox continued: "It was just about how he saw my game and how he could see me reaching my potential at Northampton.
"As a footballer, you always want to play at the highest level you can and play as well as you can for as long as you can and he spoke about wanting to develop me as a footballer and winning matches.
"I obviously experienced a promotion last season and now I'm aiming to do it again. I want to win games of football and make things happen and hopefully, whilst working with the gaffer, that's something we can do together. The club has got a good record of improving players and that's what I want – to kick on and keep improving.”
Fox was not involved when Cobblers cruelly missed out on promotion at the end of last season – but he was well aware of what went on.
He added: "I was paying attention to what happened on the last day of the season and it was crazy! Football can be crazy and it was heartbreaking for the club but that's the way it goes sometimes.
"I'm a fresh face to the squad now but I think the message from the manager is that we are ready to go again and go one better next season.”