The Italian league voted against adopting a collective contract signed by the players on Wednesday, raising the possibility of a Serie A strike.
The league voted 18-2 against the contract, standing firm in its desire to make two changes.
The clubs want to allow coaches to force unwanted players to train away from the first team. They also want players to pay a new solidarity tax that applies to high earners.
"The text signed by the players' association can't be signed if those two points are not integrated," Serie A president Maurizio Beretta said.
The players announced this month that they will strike if a new collective contract is not signed before the season opens. The conflict between the players and the league has been ongoing since the last collective contract expired in June 2010.
Cagliari and Siena were the two clubs that voted in favor of the contract.
After the vote, the Italian soccer federation delayed a meeting from Wednesday to Thursday.
"At the moment the conditions are not right to play," players' association president Damiano Tommasi said, according to the ANSA news agency. "The league's requests are (being used as an excuse). The federation meeting was postponed but I don't see what could change."
The players set two strike dates during the first half of last season, both of which were avoided with last-minute verbal agreements.
Serie A is expected to start on Saturday with Fiorentina at Siena in a Tuscan derby and defending champion AC Milan at Cagliari. On Sunday, it's: Napoli vs. Genoa; Atalanta vs. Cesena; Bologna vs. Roma; Inter Milan vs. Lecce; Lazio vs. Chievo Verona; Novara vs. Palermo; Parma vs. Catania; and Udinese vs. Juventus.
A strike by Spanish club players has already wiped out the opening weekend of the Liga.
While there have been numerous other threats over the years, the only time Serie A players went on strike was in March 1996. Among the issues then was the Bosman ruling, which established the right of players to switch clubs freely once their contracts expired, and said strict limits on foreigners were illegal.