Manchester City needed a 90th minute penalty to get all three points against Borussia Moenchengladbach, while Madrid, PSG and Juventus all recorded wins.
Moenchengladbach opened the scoring in the 54th minute through Lars Stindl, before City equalised through a controversial own goal.
City defender Demichelis had his appeals for a goal ignored, as his shot from a corner clearly crossed the line before 'Gladbach was able to clear the ball. However, it proved insignificant, with City scoring from the follow up shot, which took a deflection before finding its way into the bottom of the net.
Sergio Augero then scored from the spot late in the match to give his side the win.
Benfica recorded the biggest upset of the night, beating Atletico Madrid away from home 2-1.
Meanwhile, Real Madrid star Cristiano Ronaldo notched his 500th and 501st career goals, as his side beat Malmo 2-0 to remain top of Group A.
Full Wednesday night Matchday two results:
Ukraine Shakhtar Donetsk 0 - 3 Paris Saint-Germain (Aurier 7, David Luiz 23, Ibrahimovic 90)
Malmo Real Madrid (ESP) 0 - 2 (Ronaldo 29, 90)
Manchester United (Mata 34-pen, Smalling 53) 2 -1 VfL Wolfsburg 1 (Caligiuri 4)
CSKA Moscow (Musa 7, Doumbia 21, 36-pen) 3 - 2 PSV Eindhoven (Lestienne 60, 68)
Astana (Hakan Balta 77-og, Canas 89) 2 - 2 Galatasaray (Bilal Kisa 31, Eric 86-og)
Atletico Madrid (Correa 23) 1 - 2 Benfica (Gaitan 36, Goncalo Guedes 51)
Borussia Moenchengladbach (Stindl 54) 1- 2 Manchester City 2 (Christensen 65-og, Aguero 90-pen)
Juventus (Morata 41, Zaza 87) 2 - 0 Sevilla