Watched by a crowd of 272 at Bashley Road, the Stags deservedly came on top thanks to twin headers from Sherborne and on-loan AFC Bournemouth centre-back Lewis Lindsay.
The victory pulled Steve Riley’s men four points clear of the Foresters in third-to-bottom spot and they will head into Saturday’s home game against promotion-hunting Cambridge City having picked up seven points from their last three games.
Sherborne, back after long-term injury, struck after 14 minutes, bravely putting his head in where it hurt to bury Harrison Gilkes’ cross.
Totton made the points safe with 14 minutes remaining with Lindsay climbing highest to nod home Liam Gilbert’s corner.
“It wasn’t much of a spectacle,” admitted Riley. “It was quite a heavy pitch, which made it difficult for both teams.
“Bashley hit the bar before Sherbs scored, which was maybe the bit of luck we needed, but that was their only real chance of the first half.
“As a team we snuffed them out well and when I spoke to (Bash co-boss) Paul Gazzard afterwards, he said we were the better side which is always nice to hear.
“I’d demanded a better return from set pieces, so it was good to see Lewis Lindsay’s header go in from a corner.
“After a 4-3 (at Banbury) on Saturday, the clean sheet was massive for us tonight.
“I wouldn’t call it an ugly win, but it was all about hard work and resilience.”