Febian Brandy was the toast of the town after securing Walsall's 2-1 win over Flynn's title-chasing team.
The former Manchester United man capped an excellent second-half performance when cutting past defender Tommy Spurr in the 82nd minute to beat keeper Gary Woods and sentence Rovers to back-to-back defeats,
"I thought the defeat at Bury was a one-off and we kept things pretty low key at the training ground," said Flynn.
"But unfortunately it wasn't a one-off and I spotted some danger signals that need to be dealt with and will be.
"We have to galvanise ourselves ahead of Tuesday home game against Mk Dons and we have got to get back to doing what we have been doing from most of the season, which are the right things.
"It was a good link up between Chris Brown and Billy Paynter for our goal and Billy finished it off well.
"We started to come back into the game around that time and we had our best spell of the game between then and half-time.
"Credit to Walsall, they came with a game plan and they caught us out."