EXCLUSIVE

Alex Rodriguez' expensive publicist is sneakily trying to torpedo MLB's case to suspend A-Rod over his alleged steroid usage ... so says MLB ... and now the league wants the court to hold the publicist in contempt.

MLB just filed legal docs in A-Rod's ongoing appeal of his 211-game suspension for using banned substances, claiming the Yankees star's publicist is refusing to fly from L.A. to New York to testify in the case ... despite a subpoena ordering him to do so.

According to the docs, Michael Sitrick doesn't want to fly 2,400 miles because it would be "overly burdensome and unfair" ... even though Sitrick's PR company has an office there.

Sitrick's people have offered to make him available via video chat, but MLB is demanding he appear in person.

A judge has since ruled that Sitrick MUST comply with the subpoena ... so Sitrick has filed an appeal of his own in federal court, asking to be excused from flying to NYC. Now, MLB wants a judge to hold Sitrick in contempt and fine him for every day he refuses to show up.

The arbitrator in A-Rod's appeal must make a decision ASAP -- whether to uphold, overturn, or reduce his suspension -- but MLB officials think Sitrick is trying to run down the clock ... in order to force the arbitrator to make a ruling without his testimony.

Although Sitrick said he'd appear by video chat ... ya gotta think he knew MLB lawyers would never accept that -- so he gets to look like the good guy, while effectively stalling.