For a cautious Steve Cotterill, it was nothing more than the first tentative step rather than a giant leap.
Nonetheless, Doncaster represented a fourth clean sheet in 34 matches this season for Pompey.
Now he’s hoping the seventh central-defensive pairing employed by the Blues during the current campaign can finally be the answer to his long-running conundrum.
Ricardo Rocha was drafted in for the Keepmoat Stadium trip to partner Greg Halford for the very first time.
The Portuguese defender took full advantage of his first start in seven matches by emerging as the cornerstone in a 2-0 success.
Before then, the combinations of Marc Wilson/Ibrahima Sonko, Sonko/Halford, Aaron Mokoena/Halford, Mokoena/Sonko, Mokoena/Rocha and Sonko/Rocha had featured in various starting combinations this season.
In addition, many more have been utilised during matches at different stages after coming on as substitutes.
Inevitably, it is too soon to proclaim whether the solution has been found in the form of Rocha and Halford.
Yet first impressions were certainly favourable among the large Pompey contingent present at Doncaster on Saturday.
For Cotterill, though, after so many defensive false dawns, it is clear there is much still to be done before declaring this double act the Blues’ real deal.
He said: ‘I thought Ricardo (Rocha) played well in just another central-defensive partnership.
‘That is seven different central-defensive partnerships named in starting line-ups. There will be a dozen within games that have changed around.
‘That is what you need to try to build your team on. We haven’t been able to get that right all season.
‘We didn’t have any defender at the club when I walked into the door – and we were under embargo.
‘But on Saturday we did keep a clean sheet which is important, for sure.
‘They did well and we are pleased with that but we’ve got to remember it’s one game, nothing more.
‘You haven’t just got to do that Saturday, you’ve got to do that next week, and then so on and so forth after that.
‘I was happy with them. A couple of times when balls were delivered into the box I didn’t feel as though we got our spaces right, but that is something for us to work on this week.
‘It just gives us that base to work with.’
Pompey never appeared in any danger of surrendering a two-goal advantage once Joel Ward had netted in the 52nd minute with a sublime lob.
Marshalled superbly by Rocha and Halford, the defence were also indebted to Ritchie de Laet, who enjoyed his best display since his debut at Nottingham Forest.
Meanwhile, Hermann Hreidarsson made it three matches on the spin as he continues his comeback from a career-threatening Achilles tendon injury.
Injuries permitting, the likelihood is all four will retain their places for the visit of Barnsley this weekend.
That would be regardless of whether Aaron Mokoena will have his work permit settled in time.
But, despite their impressive showing as a defensive unit, Cotterill admits he still felt plenty of nervy moments watching from the dugout.
He added: ‘I wouldn’t say we were comfortable throughout.
‘Sometimes when you are not in the technical area you can look at it and think Portsmouth were comfortable.
‘Your heart won’t beat like my heart does when the ball goes in our box.
‘You don’t want it to drop the wrong way to somebody from the opposition.
‘Someone doesn’t even have to get a perfect strike and it gets a ricochet and ends up in the back of your net.
‘Then, all of a sudden – at 2-1 – it’s game on again so we needed to make sure we kept a clean sheet.
‘We desperately didn’t want them to get a goal that would give the crowd a bit of a fillip and get back into the game.’