An Achilles tendon injury had kept Olosunde sidelined since a summer move from Rotherham United but he got his chance here with injury ruling Sepp van den Berg out.
Andrew Hughes and Tom Barkhuizen were also missing through injury, with Patrick Bauer only fit enough for the bench.
The centre of defence had a different look, with Jordan Storey, Liam Lindsay and Greg Cunningham forming the three.
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Ched Evans came in for Sean Maguire up front having scored twice off the bench in the last two games this Evans' first start since August
There was a place on the bench for Joe Rafferty in the Championship for the first time this season.
Blackburn: Pears, Lenihan, Hecke, Wharton, Nyambe, Travis, Rothwell, Pickering, Buckley, Khadra, Brererton Diaz. Subs: Johnson, Davenport,, Dolan, Butterworth, Clarkson, Edun, Eastham.
PNE: Iversen, Storey, Lindsay, Cunningham, Olosunde, McCann, Whiteeman, Browne, Earl, Riis, Evans. Subs: Bauer, Johnson, Rafferty, Ledson, Maguire, Sinclair, Hudson.
Referee: Gavin Ward (Surrey)
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