Man City face a potential 15 games in 64 days if they are to make history and win the quadruple. They now know exactly what they have to do.
Liverpool got the jitters but are back on top of the Premier League, while two successive defeats mean the road is looking more rocky for Man Utd.
Manchester City will face Brighton & Hove Albion and Watford will face Wolverhampton Wanderers in the semifinals of the FA Cup.
Brighton scored twice in the final two minutes, as Millwall's keeper handed them a late equaliser, and then won on penalties to seal FA Cup progress
After successive defeats, Man United's caretaker manager must ensure his players hit the ground running after the international break.
The Norwegian said his team's performance in the 2-1 defeat at Molineux was the "poorest" of his time in charge at Old Trafford.
The worst performance under Ole Gunnar Solskjaer saw Man United featured defensive mistakes and a lack of attacking intent.
Wolves knocked Manchester United out of the FA Cup at the quarterfinal stage with a 2-1 win at Molineux to book a spot in the semifinals.
City kept up their quadruple hopes when they beat Swansea City 3-2 in the FA Cup quarterfinals with the help of two controversial decisions.
Man City kept their hopes of a quadruple alive, but it was thanks to Sergio Aguero who helped them back from 2-0 down against Swansea in the FA Cup.
Sergio Aguero scored an 89th-minute winner as Manchester City kept their Quadruple hopes alive by coming from 2-0 down to win 3-2 at Swansea.
Watford reached their second FA Cup semi-final in four seasons with substitute Andre Gray sealed a 2-1 win over Crystal Palace.
Manchester City manager Pep Guardiola believes that the club's achievements in the Champions League will ultimately determine if his stint in Englan
Manchester United interim boss Ole Gunnar Solskjaer has the same principles of hard work and positivity as former manager Alex Ferguson and that has
Midfielder Nemanja Matic has told ESPN FC Manchester United's players see stopping Man City's quadruple bid as an extra incentive in the FA Cup.
The Catalan coach won the trophy twice during his time at Barcelona, but has only reached the quarterfinals with Man City.