Oscar celebrates after scoring for Chelsea
Manchester United survived a scare from Galatasaray to win their opening Champions League game in Group G thanks to Michael Carrick's early goal, while Barcelona needed a late rally to come from 2-1 behind to beat Spartak Moscow 3-2.
And at Stamford Bridge, champions, Chelsea threw away a two goal cushion to draw 2-2 with Italian champions, Juventus, while Celtic played goalless with Benfica.
At Old Trafford, the Turkish side were denied what appeared to be a clear penalty when Nemanja Vidic fouled Umut Bulup.
Carrick put United ahead after a neat move but Galatasary hit the woodwork twice before Nani saw a weak spot-kick saved by Fernando Muslera.
Selcuk Iman headed against a post but United held on for a scrappy victory.
At the Bridge, Chelsea squandered a two-goal lead as they began the defence of their Champions League title with a draw against Juventus at Stamford Bridge.
Oscar handed Roberto Di Matteo's side a 2-0 advantage with a long-range shot that went in via a deflection followed by a stunning second.
Juve hit back just before the break through Arturo Vidal, who fired in a low strike from 18 yards.
Fabio Quagliarella equalised late on when he slid his shot past Petr Cech.
The Italian champions and current Serie A leaders also went close when forward Mirko Vucinic flashed a shot narrowly wide, while midfielder Claudio Marchisio had an effort blocked by keeper Cech.
In other games, Bayern Munich beat Valencia 2-1, Braga lost at home 2-0; BATE upstaged Lille 3-1 and Shakhtar 2-0 Nordsjaelland
RESULTS
Barcelona 3 - 2 Spartak Moscow
Bayern Munich 2 - 1 Valencia
Braga 0 - 2 CFR Cluj-Napoca
Celtic 0 - 0 Benfica
Chelsea 2 - 2 Juventus
Lille 1 - 3 BATE Borisov
Man Utd 1 - 0 Galatasaray FT
Shakhtar Donetsk 2 - 0 FC Nordsjaelland