Damian Lane believes a Melbourne Cup chance might have gone begging after Mer De Glace finished sixth after over-racing in the 3200m race.

Damian Lane's bid for an unprecedented feat has fallen short, with the star jockey left to ponder what might have been in the $8 million Melbourne Cup.

Lane had already ridden the winner's of the Golden Slipper, Caulfield Cup and Cox Plate during 2019 and was aiming to add Tuesday's Melbourne Cup which would have been a feat achieved by no other rider in the same year.

But Lane and Caulfield Cup-winning Japanese horse Mer De Glace finished sixth in Tuesday's Flemington showpiece won by Craig Williams on the Danny O'Brien-trained Vow And Declare.

"He was massive. He ran so well," Lane said.

"He just never settled at any point. He pulled his head off the whole race on the slow speed and I had a chequered passage getting through them.

"I still thought when I got out he was really going to fly and challenge but he just emptied out because he had done too much against me in the run.

"Had he had a genuinely run race - you could probably say that for a few of them - if you run the race a few more times with even luck he can win."

Lane won the Golden Slipper in Sydney in March on Godolphin's Kiamichi, while the Hisashi Shimizu-trained Mer De Glace took out the Caulfield Cup before Lane added the Cox Plate on star Japanese mare Lys Gracieux.

The 25-year-old felt missing out on creating history on Tuesday was not really the disappointing part, rather he considers it was his best chance yet to win Australia's most famous race for the first time.

"I guess the disappointing part is that you don't get a chance with that good a ride in the Melbourne Cup very often," Lane said.

"They're not easy to get on. Unfortunately an opportunity might have gone begging.

"But I couldn't be more proud of the horse."

Mer De Glace was Lane's fifth ride in a Melbourne Cup and his best finish so far with his previous best a seventh on Beautiful Romance in 2016.