Players union chief Gordon Taylor says England should have walked off in the game with Spain after racist abuse from home fans towards their black players.
The Football Association is to complain over the incidents but Taylor says it should have acted at the time.
The chief executive of the Professional Footballers' Association told the BBC: "My members were being humiliated."
But Uefa said England's players were right not to walk off the pitch in protest at the crowd's behaviour.
Taylor said he was appalled that monkey chants were directed at Ashley Cole and Shaun Wright-Phillips, while several England U-21 players were targeted in their game on Tuesday.
"The message should have come from the FA directors to say we will take responsibility and take them off," he said.
Taylor added: "We have to say 'enough is enough' and set an example. It's about human dignity.
"We should have set an example in that the game is more important than winning or losing."
But Uefa spokesman William Gaillard, told BBC Radio Five Live that leaving the pitch would have set a precedent.
"We would not condone such behaviour for the very simple reason it could lead to all sorts of abuse," he said.
"I don't think we should advise this kind of behaviour for merely technical reasons, because we would have hundreds of cases in which players could walk off the pitch and say 'I heard someone shouting something'.
"I don't think this is the right attitude."
The match fell under Fifa authority rather than that of Uefa as it was a friendly - but the FA is writing to both authorities as Uefa is responsible for the leading the campaign against racism in European football.
Gaillard denied that Uefa's punishments for racist chanting are too lenient.
Referring to a hypothetical situation in European club football rather than last night's clash, he added: "It would be unfair to kick out a whole club because of the behaviour of a few fans."