The 18-year-old striker came off the bench to good effect against Gillingham last weekend - helping his side recover from two goals down to earn a point.
Mandeville was not initially named in the matchday squad but an injury to Nathan Tyson in the warm-up meant he was a late addition to the teamsheet.
Ferguson has spoken several times recently about his interest in adding another forward player to his squad - one who offers something different to senior attacking trio Andy Williams, Tyson and Curtis Main - before the current transfer window closes.
The Scot would like to add someone capable of playing in between the lines, but only if the player and the deal is right for Doncaster.
But Rovers’ boss said after last weekend’s 2-2 draw with the Gills that Mandeville, who spent a month on loan at Whitby Town prior to the turn of the year, could potentially save the club an additional outlay.
“Mandeville was outstanding when he came on. He was really, really, really, really good,” said Ferguson.
“He’s gone out on loan and maybe it was just the little kick up the backside he needed.
“He’s come back and he’s been brilliant in training.
“It’s funny how it works, he wasn’t even meant to be on the bench [on Saturday] but he’s come on and made a big impact in changing the game.
“He’s played in between their lines really well.
“I’ve been groaning on about needing a player that’s a little bit different but he might have solved the problem for me.
“I thought he was excellent when he came on, he was really positive for us.”