Balotelli, who joined City from Inter Milan last week for around €29m, started on the bench before coming on as a 57th minute substitute for Gareth Barry. In the 72nd minute, moments after Yaya Toure had hit the post, Balotelli capitalised on some fine work by Emmanuel Adebayor to fire the ball into the top corner. He went on to pick up a yellow card as City got an important away win.
There was good news for the other English teams in action as well with Ryan Babel's goal on the stroke of half-time giving Liverpool a 1-0 win over Turkey's Trabzonspor. Roy Hodgson's side should have had more but Christian Poulsen had a goal disallowed and Joe Cole missed a penalty.
Aston Villa shrugged off the recent departures of coach Martin O'Neill and star midfielder James Milner to grab a useful 1-1 draw against Rapid Vienna in Austria. Villa made an excellent start when winger Marc Albrighton crossed for Barry Bannan to tap home from close range in the 12th minute. The home side hit back though to level just after the half hour when Atdhe Nuhiu glanced in Steffen Hofman's cross.
In Glasgow, Celtic took a valuable 2-0 lead from their first leg game against Utrecht. The Bhoys opened the scoring in the 19th minute through Mexican midfielder Efrain Juarez before Greece striker Georgios Samaras fired in the second in the 34th. Neil Lennon's team were unable to add any more after the break but will be happy to have a handy cushion heading back to the Netherlands.
The two other Scottish sides in action both lost, however. Dundee United were beaten 1-0 at home by Greek side AEK Athens - Algerian striker Raffik Djebbour netting the only goal of the game - while a late effort from Tom Hately threw Motherwell a lifeline as they went down 2-1 at Odense in Denmark.
Veteran German midfielder Michael Ballack made his first appearance for new club Bayer Leverkusen since his summer move from Chelsea. Coming on in the second half, Ballack, who missed the FIFA World Cup™ because of an ankle injury, scored from the penalty spot in Leverkusen's comfortable 3-0 win over the Ukrainians of Simferopol.
Juventus needed a last gasp winner from Amauri to sneak a 2-1 win at Sturm Graz in Austria. French Cup winners Paris St Germain cruised to a 2-0 win over Maccabi Tel Aviv while Lille were held to a goalless draw at Romanian side Vaslui.
Russian side Sibir Novosibirsk collected a notable scalp as they beat PSV Eindhoven 1-0. Both sides were down to ten men by half-time with the winner coming two minutes into added time at the end of the game through Aleksandr Degtyarev. Another Russian side CSKA Moscow all but booked their passage to the group stage with a 4-0 home win over Cypriot outfit Anorthosis Famagusta.