The Blues’ head coach made a bold decision by turning to the formation he ditched following last month’s 4-0 humiliation against Ipswich.
Since then, his side have embarked on an eight-match unbeaten run and won five straight games.
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It was an outcome which also marked the surprise return of the 3-4-3 – with excellent results.
Cowley told The News: ‘We wanted balance and couldn’t find it in a back four.
‘We thought Reeco could play left wing-back, he’s probably not a left-back, and I thought he did great against Lincoln, I am so pleased with him.
‘We literally spent the last two days watching everybody's Wyscout videos of them playing left-back.
‘I think Mahlon Romeo had 11 minutes at Leicester in 2017, Kieron Freeman had 51 minutes in 2016 for Sheffield United, Reeco had played a little more recently, Sean Williams had played there at Millwall under Ian Holloway, but there wasn’t a perfect solution.
‘I said at the time I didn’t think it was the formation, yet the safest decision would have definitely been to keep the back four.
‘Although the bigger risk was not to be brave and I will always do what I think is right, even if I won’t always be right.
‘It was also a staff decision, we always study as hard as we can to get the right decision.
‘For what we had available, I thought it was the perfect system and absolutely we will use it again.
‘We are always open minded in terms of formations.’
Pompey remain in ninth place, yet now lie just three points adrift of the League One play-offs following a remarkable resurgence.
And their latest scalp in the nine-match unbeaten run was Michael Appleton’s Imps.
Cowley added: ‘It was the right system to play against Lincoln because they are a team that, if they get control of possession, rhythm and flow, can be very difficult.
‘So we had to lock onto both of their centre-halves, lock onto their number six, jump our wing-backs and press really aggressively – and they couldn't’ get any flow in their performance.
‘That's why we had the control we had.’
A message from the Editor, Mark Waldron
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