By ESPNSTAR.com staff
Bielsa was furious construction at the club's Lezama training facility was not completed in time for the start of pre-season and got involved in a heated row with construction staff.
Later, he publicly slammed the company responsible and accused them of not respecting the contract which had been signed.
"The condition of Lezama is an insult to the players and I am responsible for them," Bielsa said.
"I was indignant because that was not recognised and began to say offensive things. I don't respect him because he did a bad job."
However, Athletic responded by distancing themselves from their manager's comments and issued a statement that construction work had been conducted in a satisfactory manner.
"Athletic Bilbao do not share the personal and subjective opinion expressed by Marcelo Bielsa in [Thursday's] press conference with regards to the construction work, the extent to which the contract has been honoured and the professionalism of the people involved," a club statement read.
"We would like to state that the works contract has been fulfilled correctly up until the current date, so we would like to publicly apologise for any damage that the comments made by an employee of this club may have caused to the construction company and its workers."
Reports suggest that Bielsa has handed in his resignation letter over the club's lack of support for him over the construction issue.
The 56-year-old Argentinian was praised throughout the 2011/12 season for guiding the Basque team to the finals of both the Europa League and the Copa del Rey, as well as a 10th-placed finish in La Liga.
He agreed a contract extension which will keep him with the La Liga club until June 2013 only last month.