Manchester United and Aston Villa paid a heavy price for having men sent off on in the Premier League on Sunday with United losing a tight derby to Man City and Villa surrendering a lead in defeat by Tottenham Hotspur.
Sergio Aguero condemned United manager Louis van Gaal to a 1-0 defeat in his first Manchester derby after defender Chris Smalling saw red for the visitors before halftime.
Villa scored a first goal in six games to take the lead at home to Tottenham but then had Belgian striker Christian Benteke dismissed for a moment's indiscipline and conceded two late goals to go down 2-1.
The Manchester clubs' 151st league meeting was decided by a goal from Argentina's Aguero in the 63rd minute.
With Rafael Da Silva missing the game, Smalling sent off and then Marcos Rojo forced off in the second half with a shoulder injury, a makeshift United defence comprising Antonio Valencia, Michael Carrick and teenagers Paddy McNair and Luke Shaw came under increasing pressure.
The surprise was that City were pushed back and suddenly looked edgy once they had scored.
In the end, champions City were pleased to hang on for a fourth successive league win over their neighbours -- the first time that has happened since 1970.
The other depressing historical note for Van Gaal was that he has now presided over United's worst start to a season since 1986, when Ron Atkinson was sacked and Alex Ferguson appointed.
The result left United in ninth place, with 13 points from 10 games and no away wins.
City, meanwhile, returned to within six points of leaders Chelsea and two behind surprise second-placed team Southampton.
Smalling picked up a foolish yellow card for raising his foot in attempting to block a clearance by City goalkeeper Joe Hart and seven minutes before halftime he clearly fouled James Milner and was dismissed.
"I didn't see the first yellow, but as a player if you know you have a yellow card you have to deal with that problem," Van Gaal said.
"I don't think he dealt with it very smartly."
Villa boss Paul Lambert was upset with the decision to send off Benteke -- a major turning point in the match -- after a melee involving Tottenham's Ryan Mason.
"I'm not condoning what Christian did, as you can't raise your hands, but he was provoked as well," he told Sky Sports.
Villa scored for the first time since September 13 through Austrian Andreas Weimann in the 15th minute.
Fortunes changed after Benteke was dismissed.
In the last 10 minutes Nacer Chadli equalised and just before stoppage time substitute Harry Kane, who had replaced Emmanuel Adebayor, drove in a free kick that was deflected in off Nathan Baker.
It was Kane's first League goal of the season, to add to eight in the Europa League and League Cup.
Defeat would have left Tottenham in a parlous position but the late transformation shot them up to eighth place and left Villa 15th, only two points above the relegation places after a sixth successive defeat.