Match ends, Huddersfield Town 2, Nottingham Forest 1.
Huddersfield Town boss Danny Cowley accused Nottingham Forest's staff of showing "a lack of respect" and said the Reds "wanted to kick us" after seeing his side edge a fractious match.
The Terriers secured a second victory in three games to extend Forest's winless run to five thanks to a set-piece goal either side of the interval.
Christopher Schindler's fierce volley opened the scoring before tempers boiled over at the end of an increasingly niggly first period, with Cowley and Reds counterpart Sabri Lamouchi confronting each other amid ugly scenes near the tunnel.
Steve Mounie's header added to the Forest frustration when he doubled the lead within five minutes of the restart and they held on for victory after Joe Worrall's header made it 2-1, before further confrontations followed between players and staff at the end.
Christmas cheer disappears
Cowley said: "Forest were physical and, in that moment, you either step back or step forward. We stepped forward. No one will come here and beat us up. We stood up for ourselves, I'm proud of the players for that.
"They came here and wanted to kick us, but no one is going to bully us. You have to have substance. I was a bit disappointed with their staff, they showed a lack of respect.
"Here was me thinking it was Christmas and good will to all men, but I was wrong. I'm really pleased for Steve Mounie. He came in and did extra work on his finishing during the week and sometimes, like today, you get what you deserve."
A strong Forest fightback in the closing stages saw them come close to grabbing a draw, but Town held on for a win which takes them six points clear of the relegation places.
Lamouchi was not as forthright in his views, but said he was "surprised" by the altercations which greeted both the half-time and full-time whistle.
He told BBC Radio Nottingham: "There was some confusion and tension. This can happen. I was surprised. But if it was a tactic, I'm not sure it's a good tactic. But congratulations to them for the victory.
"I was surprised. Football is enjoyment and respect. We need respect for the opponent, for the referee. There was a little bit of tension. But I just want to focus on the pitch, on my players."
A bright Forest start, which saw both Matty Cash and Sammy Ameobi go close, came to nothing and the Terriers took control from the moment German centre-half Schindler reacted first to net when Trevoh Chalobah's initial effort was blocked following a corner.
The half-time shenanigans as the players made their way off the pitch were still fresh in the mind when the hosts scored from another corner, with Mounie leaping at the back post to power in a close-range header from Karlan Grant's corner.
Huddersfield then dominated and had chances to make the game safe, notably through Grant, who saw a shot well saved by keeper Brice Samba.
The lively Joe Lolley helped spark a strong Forest response in the closing quarter, with some smart thinking seeing his quick corner headed in at the near post by Worrall.
Lolley then saw a decent strike kept out by a fine-one handed stop by Kamil Grabara, who also denied Cash with a fabulous save in stoppage time.
But Forest could not force a leveller as they piled forward late on, with their defeat just their second in 13 away from home in the league.
"What I said at the break was 'don't become crazy' and we will come back. Unfortunately it was not the case. It's a very bad moment but we need to stay together," added Lamouchi.
"We started in a good way and created some chances and we deserved to score first, but we need to be more efficient in the box. It was a story of three corners and three goals.
"I'm upset, but we've just got to keep working. It's a very bad moment, but we need to stay calm, work again and stay focused. We will come back."
The Reds are only three points off the play-off places despite a miserable run which has brought three defeats in five, including a 4-0 hammering at home to Sheffield Wednesday last Saturday.
- 1GrabaraBooked at 80mins
- 9KachungaSubstituted forKoromaat 79'minutes
- 6HoggBooked at 69mins
- 8ChalobahBooked at 63mins
- 7BacunaSubstituted forBrownat 87'minutes
- 3FigueiredoBooked at 57mins
- 21SowBooked at 39minsSubstituted forSemedoat 68'minutes
- 8WatsonBooked at 66minsSubstituted forYatesat 86'minutes
- 19AmeobiSubstituted forCarvalhoat 75'minutes
- Andy Davies
- Shots on Target
Second Half ends, Huddersfield Town 2, Nottingham Forest 1.
Corner, Nottingham Forest. Conceded by Jonathan Hogg.
Attempt missed. Tobias Figueiredo (Nottingham Forest) header from very close range misses to the left. Assisted by Joe Lolley with a cross following a corner.
Corner, Nottingham Forest. Conceded by Kamil Grabara.
Attempt saved. Matthew Cash (Nottingham Forest) header from the right side of the six yard box is saved in the centre of the goal. Assisted by Tiago Silva with a cross.
Attempt saved. Joe Lolley (Nottingham Forest) left footed shot from the right side of the box is saved in the centre of the goal. Assisted by Tiago Silva.
Foul by Tiago Silva (Nottingham Forest).
Steve Mounie (Huddersfield Town) wins a free kick in the attacking half.
Attempt saved. João Carvalho (Nottingham Forest) right footed shot from outside the box is saved in the top centre of the goal. Assisted by Tiago Silva.
Substitution, Huddersfield Town. Jaden Brown replaces Juninho Bacuna.
Substitution, Nottingham Forest. Ryan Yates replaces Ben Watson.
Offside, Nottingham Forest. Ben Watson tries a through ball, but Tobias Figueiredo is caught offside.
Corner, Nottingham Forest. Conceded by Kamil Grabara.
Attempt saved. Joe Lolley (Nottingham Forest) left footed shot from outside the box is saved in the bottom left corner. Assisted by Alfa Semedo.
Attempt blocked. Tobias Figueiredo (Nottingham Forest) right footed shot from outside the box is blocked.
Kamil Grabara (Huddersfield Town) is shown the yellow card.
Substitution, Huddersfield Town. Josh Koroma replaces Elias Kachunga because of an injury.
Foul by Alfa Semedo (Nottingham Forest).
Danny Simpson (Huddersfield Town) wins a free kick in the defensive half.