The 30-year-old has often been overlooked by Villa manager Paul Lambert and he spent last season on loan at Fulham.
Speculation has continued through the close-season that Bent will leave the club, but he proved that he could be a useful weapon as his two goals helped spare Villa's blushes at Field Mill on Thursday.
The League Two outfit had threatened to spoil Villa's pre-season opener when Alex Fisher notched shortly before the break.
But Bent restored parity in the 61st minute and made sure of the win in the final moments after Gary Gardner had put Villa ahead.
Villa opted to name two different XIs for each half, with Joe Cole and Kieran Richardson both making their debuts for the club.
The visitors started brightly and almost had an early breakthrough when Joe Bennett's effort was cleared off the line by Martin Riley.
Cole then nearly made an instant impact when he played a superb reverse pass that sent Leandro Bacuna through on goal on 20 minutes, but he was denied by the Mansfield goalkeeper.
Those misses were punished by Mansfield four minutes before the break when John Dempster got a flick on Liam Marsden's throw-in and Fisher headed home at the back post.
Lambert made wholesale changes at the break and Villa went close to a leveller when Gardner curled a free-kick narrowly wide.
The equaliser did arrive shortly after the hour mark, however - full-back Alan Hutton surged into the box and his cut-back found Bent who tapped home from close range.
Bent nearly had a second with just over 10 minutes remaining when he hit a first time shot following good work by Andreas Weimann, but his shot was stopped by the goalkeeper.
That mattered little, though, as Gardner completed the turnaround in the 85th minute. Bent and Weimann combined well and Gardner finished the slick move from eight yards.
Bent then completed the comeback when he headed home Weimann's chipped cross in the last minute.
