Guy Whittingham admitted Steve Cotterill was behind Pompey’s return to winning ways.
The Blues defeated Barnsley 2-0 at Fratton Park on Saturday night.
It was achieved by operating with two strikers and handing a central defensive recall to Ricardo Rocha.
Both moves had long been championed by supporters.
And both moves Cotterill had instigated earlier this week – prior to his departure for Forest.
The tactical switches paid instant dividends as David Norris and Luke Varney netted the second-half goals to clinch victory over the Tykes.
Yet Whittingham insisted the credit should go to Pompey’s former boss rather than himself and joint-temporary boss Stuart Gray.
The Blues legend said: ‘Obviously there were a couple of lads away during the week.
‘Liam (Lawrence) came back early and Erik (Huseklepp) didn’t come back until Thursday.
‘But all week we had been playing this way.
‘It wasn’t suddenly we decided to change things around and go 4-4-2 – we just carried on in the vein that we were.
‘Ric (Rocha) has always given his all and we like the idea of Greg on that right-hand side for a little bit. He’s got that quality on the ball.
‘It’s important when you play two up top that you can find those players up front and we felt Greg would do a good job out there for us.
‘We thought we would put Ric in there because he has trained well and been a good professional.
‘It had been planned all week – it is not something me and Stuart suddenly decided to do, it was already done. As for two up front, we haven’t played badly, we’ve just not had the occasion where we have taken our chances.
‘We just felt maybe we would get more chances with the two up front and that’s what we tried.
‘Having said that, it is about the players at the end of the day and they did extremely well for us.’
It had been an unsettling 24 hours build-up to the visit of the Tykes for Pompey.
Cotterill’s decision to walk out for Forest on Friday shook the Blues camp.
Nonetheless, they shrugged off the saga to put in an excellent Fratton display in the televised encounter.
As for Cotterill, he watched from the stands at the Ricoh Arena as his new club lost to struggling Coventry.
Whittingham, though, was full of praise for Pompey’s players after bouncing back to defeat Barnsley.
He added: ‘The whole week was okay until Friday when it just blew up!
‘But that’s football, that’s what happens.
‘We know the game, things like that happen very quickly. You don’t exactly work your notice.
‘I think the players have got to take a lot of credit.
‘They all enjoyed Steve Cotterill, they worked for him and gave their all for him.
‘So for him to suddenly go and for them to give a performance like that – where they played well and won the game with a clean sheet – I think is fantastic.’