Porto's players failed to show solidarity with Moussa Marega by trying to stop the forward from leaving the field after he was allegedly racially abused, says Shaun Wright-Phillips.
The Mali international walked off the pitch during the second half of Porto's 2-1 win at Vitoria Guimaraes on Sunday in reaction to his treatment by the home fans.
However, several of his team-mates tried to restrain him, with the game being held up for three minutes before Marega was finally able to leave the field.
Speaking to Sky Sports News, Wright-Phillips slammed the behaviour of the Porto players, saying: "I think it was disgusting to be honest with you.
"For me personally, if I walk on the field with my team-mates, I'm willing to put my body on the line and my faith in them. I would want nothing less in return.
"If that had happened and I felt the need to walk off the pitch, I would hope my team-mates had my back. But they seemed to not, which was pretty hurtful to see, especially for him.
"I can imagine how alone he would have felt at that moment in time."
Marega, who also had objects thrown towards him from the crowd during the game, took to social media after the match to describe those abusing him as "idiots".
He also sarcastically thanked the referee "for not defending me and for giving me a yellow card because I defend my skin colour".
He added: "I hope I never find you on a football field again. You are a shame."
'This is really tough to watch' - Kick It Out
Football's equality and inclusion organisation Kick It Out were also critical of the reaction from Marega's team-mates.
They said on Twitter: "This is really tough to watch.
"The blatant disregard for protocol is unacceptable, and players should be united and walk off together in their condemnation of racism, instead of this. We stand with Moussa Marega."
A Porto statement said they fully support Marega's actions and called for a strong penalty against Guimaraes, who say they will investigate the incident and punish those responsible.
The Portuguese league also responded, saying: "Liga Portugal will do everything so that this, and all episodes of racism, do not go unpunished."
Wright-Phillips called for a strong punishment to be handed to Vitoria, saying: "The punishment needs to come down harder.
"I feel like they just get a slap on the wrist and they just laugh about it, and then in a few weeks it will just happen again. So until it gets punished properly, I just feel like it's going to still keep happening."
'No human being should be subjected to this humiliation'
The President and the Prime Minister of Portugal added their voices to the outcry on Monday.
Prime Minister Antonio Costa said the incident was unacceptable and urged police and soccer authorities to make an example of those responsible by handing down tough punishment.
He wrote on Twitter: "Any and all acts of racism are criminal and intolerable.
"No human being should be subjected to this humiliation. No one can remain indifferent.
"I condemn any and all acts of racism, under any circumstances.
"Total solidarity with Marega, who in the field proved to be not only a great player, but also a great citizen."
President Marcelo Rebelo de Sousa said: "Portugal's Constitution very clearly condemns racism, as well as any other forms of xenophobia and discrimination."