Udinese inflicted more misery on hapless Tottenham Hotspur with a 2-0 UEFA group stage victory on Thursday over the London side who contributed to their own downfall through poor goalkeeping and ill-discipline.
Competition favourites AC Milan brushed aside Heerenveen 3-1 to make a confident start in Group E while Sevilla, winners in 2006 and 2007, eased to a 2-0 home win over VfB Stuttgart in Group C.
In-form Udinese's victory over Spurs increased the pressure on under-fire Spanish coach Juande Ramos, whose side prop up the Premier League and failed to finish with 11 men for the second successive match.
Udinese, second in Serie A, were gifted the chance to take the lead midway through the first half when Tottenham keeper Heurelho Gomes failed to clear a backpass and then fouled Fabio Quagliarella to stop the Italian striker gaining possession.
Fellow Italian international Antonio Di Natale swept home the penalty. Spurs, who had two players sent off in their defeat by Stoke City at the weekend, were reduced to 10 men just before the hour when Jamie O'Hara was booked twice in a minute.
A swift break secured the Group D points for Udinese four minutes from time with Simone Pepe firing home.
Milan took a full-strength squad to Heerenveen and Carlo Ancelotti's side made class count, stamping their authority on the game with two goals in the first 23 minutes.
An own goal from defender Calvin Jong-A-Pin, who diverted in Kaka's cross, and a rare appearance on the scoresheet by midfielder Gennaro Gattuso put Milan in control.
Filippo Inzaghi made it 3-0 after 69 minutes, prompting Ancelotti to bring off Inzaghi, Kaka and Shevchenko and replace them with Ronaldinho, Marek Jankulovski and Alexandre Pato.
Sampdoria completed a fine night for Serie A sides, winning 2-1 at Partizan Belgrade in Group C.
CSKA Moscow's talented teenage playmaker Alan Dzagoyev scored twice as the 2005 winners opened their Group H campaign with a 3-0 win at home to Deportivo Coruna.
Dzagoyev, who made his debut for Russia in a World Cup qualifier against Germany this month, struck twice in three first half minutes for CSKA, unbeaten in the Russian league since July 20. Brazilian Vagner Love added a third on the hour.
This is the last season at the helm for coach Valery Gazzaev, who led CSKA to their first European trophy when they beat Sporting in the 2005 final. He said in July that he would step down when the Russian season finishes in November.
Aston Villa got the better of Ajax Amsterdam in a pulsating clash between two former European champions as they edged their Group F rivals 2-1 at Villa Park.
Skipper Martin Laursen nodded Villa ahead from an Ashley Young corner before the hosts then conceded an equaliser in identical fashion when Belgian Thomas Vermaelen was left unmarked to direct in Urby Emanuelson's corner.
Gareth Barry restored Villa's lead seconds before halftime.
"For the first match in the group stage I think it was a wonderful win against a very, very good side," Villa manager Martin O'Neill told Channel Five TV.
Bundesliga leaders Hamburg and German rivals Schalke 04 recorded opening group stage victories.
Hamburg won 2-1 in Slovakia against Zilina in Group F with Croatian internationals Mladen Petric and Ivica Olic getting their goals, while 1997 winners Schalke 04 brushed aside Paris St Germain 3-1 in their Group A tie in Gelsenkirchen.
Australian Harry Kewell headed the only goal in the first half to earn 2000 winners Galatasaray a 1-0 Group B win over Greece's Olympiakos Piraeus in Istanbul.
The top three teams from each of the eight groups progress to the first knockout round where they will be joined by the eight sides finishing third in their Champions League groups.