Apologies, by "shocking" we mean "hilarious".
The incident happened ahead of Chelsea's Champions League clash with Paris Saint-Germain, which ended 1-1.
But West Ham fans took the opportunity to mock the entire thing with a short clip uploaded to the internet.
Comedy as a weapon against hate. Very funny.— Russell Brand (@rustyrockets) February 22, 2015
A Metropolitan Police spokesman said the three men had now been identified and the force was liaising with the French authorities.
None of the men sought by Scotland Yard have been arrested.
A police spokesman said the force cannot arrest people for offences which happen outside the UK but "a number of people" have now been spoken to in relation to the incident.
Footage posted online showed the commuter - named in reports as Souleymane S - being pushed back on to the platform amid chants of ''we're racist, we're racist and that's the way we like it''.
Five people have so far been suspended from Chelsea's Stamford Bridge ground following investigations into the incident.
The club has reiterated its promise to ban for life anyone proved to have been involved in the altercation and is helping police in the UK and Paris.
Chelsea manager Jose Mourinho said the club were "appalled" by the racial abuse, adding that owner Roman Abramovich was also "disgusted".
But in a video posted on Twitter, online commenters accused some West Ham fans of singing an anti-Semitic song in a Jewish area, appearing to contradict the sentiments of the spoof video welcoming a black player into a train.