Chris Wood headed home the winner for Nottingham Forest in the 89th minute against Sheffield United for their first Premier League win of the season.
Wood, who had come on as a substitute, flicked a header past United keeper Wes Foderingham to send the City Ground crowd wild.
Gustavo Hamer scored a stunner on his Sheffield United debut to give the newly promoted side hope early in the second half.
Hamer, who signed from Coventry City last Friday, struck into the top corner from the edge of the box for his first goal for his new club.