However, another set of talks between the union and Serie A bosses on Friday could be more decisive in resolving a dispute over a collective contract which guarantees players' basic rights.
"Tomorrow will only be a meeting about technicalities," Campana told Reuters.
"Tomorrow there isn't the possibility of a deal. Right now the strike is on. I can confirm we are in a discussion phase and Friday could be important but at the moment I can't say we are close."
Serie A chief Maurizio Beretta and Italian football federation president Giancarlo Abete both said before a meeting between the parties on Monday that they were hopeful of stopping the strike, which would cause chaos for broadcasters and fans.
A collective contract between the union and the league expired in the close season and players have been angered by Serie A's hard-nosed approach to negotiating a new deal.
The two main sticking points are the clubs' proposals that players who are no longer wanted should accept a transfer in the final year of their contract and that players not deemed good enough should train away from the first-team squad.
"On these two particulars, there is a position we cannot accept at all. A club can't make it an obligation that a player leaves if the contracted player does not want a transfer," added Campana, a lawyer and former player with Vicenza and Bologna.
"A contracted player also has the right to train with the first team and can't be marginalised. The league has taken note of our position but I don't know what they will decide."
Several Italian football pundits such as Paolo Di Canio have criticised the players, often millionaires, for deciding to strike over such an issue when ordinary working people are struggling after the economic crisis.
The Italian game, stunned by the national team's World Cup group stage exit as holders, has only just recovered from a 2006 match-fixing scandal which severely hit the brand and experts say a prolonged strike could cause similar damage.
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