Michael Emons, BBC Sport
A rare off day for Aston Villa as they suffered their first loss in seven matches in all competitions.
Despite having far more of the ball, with 74% possession, Villa could not find a way through an organised Nottingham Forest defence, with Moussa Niakhate and Murillo defending excellently throughout for the home side.
England striker Ollie Watkins should have got his sixth Premier League goal of the campaign but failed to get a good connection on a header.
Leon Bailey fired wastefully over, Moussa Diaby has a shot saved and both Youri Tielemans and Lucas Digne missed the target on a frustrating day for Villa.
But Villa were chasing the game from only the fifth minute after Ola Aina opened the scoring and Orel Mangala added a second after Watkins had seen a shot saved by debutant goalkeeper Odysseas Vlachodimos.
This match was almost a year to the day after Unai Emery had taken charge of Villa for the first time, when the club were fearing a relegation battle but ended up qualifying for Europe for the first time in 13 years.
A sign of just how far the club has come in that time was highlighted by the fact Villa would have gone third in the Premier League with a win, but it was not to be.