The atmosphere as start time nears for the Melbourne Cup is unlike any other experience in Australasian racing.

Even the most relaxed participants are on edge and this is particularly the case for the Cup riders.  When the riders leave the jockeys’ room to mount the horses there is little of the normal relaxed conversation.

They are focussed on the task ahead and the prospect of a life-changing result.

But riding over 3200m in the largest field of the year also means that plenty can go wrong and any rider errors, or perceived errors, are now magnified by a massive television and streaming audience around the world.

As a result, it would be rare for a Cup rider not to be in peak condition on race day.

But there have been exceptions and at least one example that it is possible to ride a Melbourne Cup winner when suffering from a monumental hangover.

Champion jockey Darby Munro rode three Melbourne Cup winners, his third win coming on Russia in 1946. Russia was at 16-1 but would have been at much longer odds had punters witnessed Munro’s preliminary.

Munro, apparently by chance rather than planning, had been persuaded to join an all-night party on Cup eve and was not in great shape when he returned to his hotel at around 6am.

Legend has it that Munro arrived back at the same time as George Moore – who was riding the Cup favourite - was heading out to Flemington to ride work. Moore told Munro that he wasn’t in any state to ride that day, to which Munro replied: “George, I reckon you’re overtrained.”

But there is no doubt that Moore’s assessment was correct, as Munro’s then wife, Shirley, confirmed to Sydney Morning Herald writer Bill Whittaker, years later.

“No, he wasn’t drunk when he took Russia onto the track but he would not have passed even the most cursory breathalyser  test,” Shirley said.

Shirley had had to mount a rescue mission when Darby got back to his room. “Darby had several cold showers and an occasional ginger ale with a nip of brandy, doing his best to sober up in a hurry.

“When we arrived at Flemington we had a very long walk from the car park to the jockeys’ room. Poor Darby could barely walk. He was terribly ill.”

Fortunately, Munro ranks as one of the most naturally gifted jockeys to ride in Australia and instinct kicked in once the race started. Russia, who carried 57kg, settled beautifully in the first four, went clear on  the turn and  won by five lengths.

And what about Moore on the 4-1 favourite Cordale? He finished 10^th.

The Munro family has a wonderful record in the Melbourne Cup, with Hugh Munro and his jockey sons Darby and Jim winning six Melbourne Cups between them.

Hugh trained Revenue to win the 1901 Cup and also trained the champion mare Wakeful who ran second in the 1903 Cup with 63.5kg, conceding more than 20kg to the winner Lord Cardigan.

Darby added Cup wins on Peter Pan (1934) and Sirius (1944) and older brother Jim was successful on Windbag (1925) and Statesman (1928).

Darby was an inaugural inductee to the Australian Racing Hall of Fame and had an exceptional record in the classics and weight-for-age races. He won the Queen Elizabeth Stakes in Sydney seven times, the Warwick Stakes six time and had five wins apiece in the Cox Plate, AJC Derby and VRC Derby.

Champion trainer Tommy Smith was quoted as saying “horses would simply go faster and better for him [Munro], and he had a sixth sense when it came to tactics.”