Now the ex-Blues pair are toasting promotion to the Championship having inspired Wigan to title glory.
Whatmough and Naylor were allowed to leave Fratton Park as free agents last summer after their contracts expired – and opted to link-up with Leam Richardson at the Latics.
During their time at Pompey, under Kenny Jackett they suffered play-off semi-final defeats to Sunderland (2018-19) and Oxford United (2019-20).
While last season, following Danny Cowley’s arrival as interim head coach in March 2021, a final-day defeat to Accrington saw them tumble out of the play-off positions at the death.
Now they will play in the Championship next term, representing a first opportunity at that level for Whatmough.
And the central defender who hails from Gosport made a tongue-in-cheek reference to his Pompey promotion record.
‘But look at us now, we couldn't be more happy.
‘It's a massive compliment to Nayls, what a player, and an even better person.
‘I remember speaking with the gaffer last summer, and he asked me about Nayls.
‘I got on to him as much as I could, really pushed for him to come here, and we managed to get it done.
‘We come as a pair, we always have done.
‘Three good years together at Portsmouth, winning the title here in our first year, and more to come.
‘He'll be coming to the end of his career before me! But I've definitely got a few more years left in me.’
Wigan claimed the League One crown after finishing two points ahead of Rotherham.
Incidentally, both teams suffered defeat at Fratton Park in the final six matches of the campaign.
Regardless, the Blues will be attempting to emulate both sides next season and escape League One after six years in residence.
Whatmough added: ‘The first conversation I had with the gaffer last summer was simple: 'Do you want to get promoted together again?
‘And I knew, no matter which players were coming in, with him behind us, it was something that was achievable.
‘I'd been involved with a championship-winning squad with him in League Two at Portsmouth, and we had a special group.
‘So I knew full well the gaffer would be putting together another special group to have a go at promotion...I just didn't know how special a group it would be!
‘But yeah, having the gaffer here was a massive reason for me joining this football club.
‘That's why there were never any second thoughts about making the move.
‘From day one of pre-season, it was all about promotion, but we were determined to keep quiet.
‘We just went under the radar, let others talk while we did our work, and we've won it.’
A message from the Editor, Mark Waldron
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