Sky Sports commentators Andy Gray and Richard Keys were caught out criticising female assistant referee Sian Massey on-air.
The Daily Mail says the pair were forced to apologise after sexist off-air comments about Massey were made public. Sky's football presenters ridiculed Massey's ability to understand the offside law before Liverpool's 3-0 win at Wolves on Saturday..
In fact, the highly-rated Massey, 25, got a crucial offside call right in the build-up to Liverpool's opening goal. Gray and Keys also criticised West Ham vice-chairman Karren Brady in remarks that were not broadcast but later leaked..
On Sunday night a Sky Sports spokesperson said: "The comments reported today are not acceptable. They were not made on air or broadcast in any way but we have spoken to Richard and Andy and told them our views. They have apologised and expressed their regret."
Speaking to each other in the studio before the game, believing their microphones were off, Keys had said: "Somebody better get down there and explain offside to her."
Former Scotland striker Gray replied: "Can you believe that? A female linesman. Women don't know the offside rule." To which Keys said: "Course they don't. I can guarantee you there will be a big one today. Kenny (Liverpool manager Dalglish) will go potty. This isn't the first time, is it? Didn't we have one before?"
