Robertson was ruled out of a game with the Hoops, who won 2-1 but lost the league to the Gers, after suffering a hamstring injury aganst Hibs the week before.
Thinking he was going to miss the Old Firm clash in 1993, Robertson was drinking with his wife.
He stayed up until 4am with pals who came over and was “p*** drunk”.
But incredibly, he was deemed fit at the last minute and played despite being tipsy.
He told Si Ferry’s Open Goal: “I was getting treatment all week and Friday night after training the players go to the hotel. We were playing Celtic on the Saturday at Parkhead.
“Rangers star admits he played ‘half-drunk’ in Celtic defeat ”
“So me and my wife had a few friends over with a few drinks and about 4 o’clock in the morning, p**s drunk I go to my bed.
“Up at 9 o’clock in the morning, go to training and I had this horrendous Hi-Tec shellsuit on.”
He added: “So I go a jog and he asks me to step it up a little bit. Half pace, three-quarter pace then sprint.
“I never thought anything of it and he says ‘OK that’s you, go get changed.’
“So I go in and have a shower and Archie comes in ‘Bill says you’re fit’.
“I’m stinking of drink, still half-drunk and I don’t like to say no.”
Celtic and Rangers are already neck-and-neck during this Scottish Premiership campaign, with the Bhoys ahead by goal difference.
The Hoops are favourites after securing their eighth consecutive league title last term.
However, the Gers have shown signs of improvement and all eyes will be on the first Old Firm clash of the season at Ibrox on September 1.