Mark Margolis has undergone brain surgery.

The 77-year-old actor suffered a fall off set during filming of 'Better Call Saul' - in which he reprises his 'Breaking Bad' role of drug cartel leader Hector 'Tio' Salamanca - and was taken to hospital, where he was whisked to theatre.

His representative told ''Doctors discovered minor brain swelling and performed a routine procedure to reduce it.''

A source told the website Mark has pulled out of upcoming mob movie 'The Neighborhood' as a result of the operation, and his condition could affect storylines on 'Better Call Saul'.

Series creator Vince Gilligan has described the actor as one of the ''finest actors alive''.

He said: ''He's one of the finest actors alive, regardless of whether the role requires him to speak or remain silent in a wheelchair, ringing a bell.''

Meanwhile, Mark was recently removed from the Best Guest Actor in a Drama Series Emmys ballot because he had appeared in five of the 10 episodes of the last season of 'Better Call Saul', rendering him ineligible for the honour.

It is also too late for network AMC to submit his name for the Best Supporting Actor category.

A Television Academy spokesperson said: ''There was an error in AMC's entry submission, and pursuant to 69th Emmy Awards rules, this entry will be disqualified. Had this not been brought to the Academy's attention now, it would have surfaced after the Nomination Round votes are tallied, during the vetting of all nominees prior to our announcement on July 13.''

The Emmys established a 50% rule two years ago in a bid to prevent recurring cast members from competing against true guest stars.

In 2010, John Lithgow won an Emmy for Best Guest Actor in a Drama Series but had appeared in every episode of season four of 'Dexter', while in 2014 'Orange is the New Black' actress Uzo Aduba picked up Best Guest Actress in a Comedy Series, even though there was only one episode she hadn't featured in.