Football fan Stephen Crean was asked “do you want to die?” before he was repeatedly stabbed by the suspected Huntingdon train knifeman.
Mr Crean, 61, felt he “didn’t have much choice” but to fight back, as he defended himself with nothing but his fists when the man approached with a “sword-type thing”.
He was returning to his south-west London home after watching Nottingham Forest’s 2-2 draw with Manchester United on Saturday, when a young woman ran through his carriage yelling “knife, knife, there’s a man with a big knife”.

Mr Crean said passengers ran down the carriage into the buffet car of the LNER train from Doncaster to London, adding: “There was nowhere to go. I didn’t have much choice.”
He said the knifeman asked if he wanted to die before he felt the knife in his arm.
“He asked me, ‘Do you want to die?’,” he told the PA news agency.
“He repeated it. Then I remember his knife going into my arm.”
Mr Crean, the son of an inner-city Dublin mother and a Roscommon father, suffered multiple injuries.
He told The Irish Times that he cherishes the childhood memories of the six weeks he and his four siblings spent in Ireland every summer to visit their cousins.
“We used to head to the seaside, up and down the coast, and we had great times. We went to Roscommon, Greystones, Cork,” he said, adding that he travels to Ireland every year as an avid Republic of Ireland football fan.
He often went to Dublin for U2 concerts in the past.
“When I get better, I’ll hopefully be going again,” he says. “I’ll always be Irish in my veins, it’s always been there and it’ll never go away.”
There were 13 casualties in total, eight of whom remain in hospital, Home Secretary Shabana Mahmood told MPs on Monday.
Mr Crean said he had no chance to escape as the armed man approached but he managed to get into a train toilet after the confrontation.

Of his decision to fight back, he said: “Probably not many people would’ve done it, but then you’re leaving people behind you vulnerable.”
He has been described as a hero and said: “It’s lovely that people are saying nice things about me.”
Mr Crean does not want to take credit for his bravery, he told The Irish Times.
“That’s the Irish upbringing for you – that’s what we do," he said. “We stand by each other. I’ll stand by my family, my friends, anyone in trouble. I’ll always be like that.
“There were probably Irish people on that train too. Of course I would protect them and of course I’d do it for anyone. I’d do it for a stranger.”
Earlier on Monday Anthony Williams, 32, appeared at Peterborough Magistrates’ Court charged with 10 counts of attempted murder after several people were stabbed on the LNER train.
He is also charged with one count of assault occasioning actual bodily harm and one count of possession of a bladed article.
Separately, Williams is charged with one count of attempted murder and possession of a bladed article over an incident at Pontoon Dock DLR station in London in the early hours of Saturday, where a victim suffered facial injuries after being attacked with a knife.
He is next to appear at Cambridge Crown Court on December 1st.