The British horse took over the lead of the race with less than 100 metres to run and jockey Corey Brown powered it home to claim his second Melbourne Cup.
He was at a loss for words after the race.
"I can't believe it. Oh honestly, I chased the ride about six weeks ago and with a light weight [thinking I was] a big chance to get on him. I can't believe it," Brown said.
"I have been back here from overseas about nine months and slowly and surely getting back to where I was. Mate, again I can't believe it."
Joseph O'Brien praised the efforts of Brown and owner Lloyd Williams.
"I can't believe it. I am thankful to Lloyd and Nick, they suggested to bring him down and he would have a good chance in the race.
"His preparation went really good. Corey gave him an unbelievable ride. For everyone and the lads at home and the lads here have done an unbelievable job.
"All the lads at home, all year round, have done a great job with him. I can't quite believe it. This is unbelievable. It hasn't sunk in yet."
Williams called it "an absolute dream".
"I am so thrilled ... It is terribly exciting. I can't put it into words to be perfectly honest.
"Just to do it with this 23-year-old [O'Brien]. He has been taking the world on.
"I thought that this horse had some chance and I thought that his run in the Ledger was good and his three-year-old form over there has been very good in the Doncaster Cup."
Although impressive in the lead up to the race, Rekindling wasn't favoured to win the Cup.
The lightly-raced 4yo has had just nine starts, all in England and/or Ireland.