Matches in Europe's premier club competition will have five officials this season after football bosses decided to extend a trial from the Europa League.
Milan should be glad of the extra two pairs of eyes after being incensed with the refereeing in Saturday's 2-0 Serie A defeat at promoted Cesena where the visitors felt they had two goals wrongly ruled out for offside and one for handball.
"We didn't play that badly. Those weren't offside," club owner and Italian Prime Minister Silvio Berlusconi told reporters.
The seven-times European champions, who have not won in six home games in Europe spanning almost two years, even put an extraordinary statement out on their website with the headline: "Without any further comment".
"Law 6 on the assistant referee reads: 'If an assistant referee is not totally sure about an offside offence, the flag should not be raised'," read the article.
New coach Massimiliano Allegri will be more concerned about Zlatan Ibrahimovic missing a penalty on debut as the pair gear up for their Champions League bows with the club.
INCREASED SPEED
The striker, signed on an initial season loan from Barcelona, has often flattered to deceive in the competition but the Swede is again expected to lead a three-pronged attack with Ronaldinho and Alexandre Pato.
Milan have a slight worry over defender Thiago Silva after the Brazilian limped off against Cesena in Milan's second league game of the campaign, where their increased speed of movement was one positive compared to last term's patchy displays.
Auxerre will enter the immense San Siro without having won a league game in this fledgling season, drawing four and losing one.
Third in France last term, they conceded an stoppage-time goal in Saturday's 1-1 draw at home to Caen and lie 17th in the standings.
"Football is sometimes cruel," coach Jean Fernandez said.
The other opening Group G game pits Real Madrid against Ajax Amsterdam.
Probable teams:
Milan: 32-Christian Abbiati; 25-Daniele Bonera, 33-Thiago Silva, 13-Alessandro Nesta, 77-Luca Antonini; 21-Andrea Pirlo, 23-Massimo Ambrosini, 10-Clarence Seedorf; 7-Alexandre Pato, 11-Zlatan Ibrahimovic, 80-Ronaldinho
Auxerre: 1-Oliver Sorin; 2-Cedric Hengbart, 6-Adama Coulibay, 12-Jean-Pascal Mignot, 23-Jeremy Berthod; 17-Benoit Pedretti, 21-Steeven Langil, 29-Delvin Ndinga, 8-Anthony Le Tallec; 14-Dennis Oliech, 18-Roy Contout
Referee: Pavel Cristian Balaj
