Scott Pendlebury and Heritier Lumumba head onto the ground for a match in 2014. Picture: Michael Willson, AFL Photos

A FORMER Collingwood-listed player has called for key club figures to speak up and acknowledge Heritier Lumumba's experience with racism.

Shae McNamara, an American who spent three seasons on Collingwood's rookie list, says he could "no longer stay silent".

The Magpies have been rocked by the leaked release of the Do Better report, which detailed a culture of systemic racism at the club.

>> THE FULL 'DO BETTER' REPORT Download the PDF here

Lumumba, a star in Collingwood's 2010 premiership season, chose not to participate in the club-commissioned review but the report's authors said there needed to be a serious investigation into his claims.

McNamara has singled out Collingwood coach Nathan Buckley, captain Scott Pendlebury and former president Eddie McGuire, as well as ex-captain Nick Maxwell and premiership midfielder Luke Ball, and wants them to validate Lumumba's experience.

"I have bitten my tongue for far too long and I can no longer stay silent in what has really bothered me," McNamara tweeted.

"The interpersonal racism happened (i.e. racist jokes, nicknames, stereotypes etc.

"(Lumumba's) not bitter because he was traded - he was traded because he wouldn't stop addressing the toxicity in the club.

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"You need to honour the effects of trauma - he felt racism his entire life, in the club, against opponents and through media/social media - everyone has their breaking points.

"This isn't about destroying the club - this is about making sure this is the last time anyone at CFC experiences what he did."

Shae McNamara during his time at Collingwood in 2010. Picture: AFL Photos

McNamara, who was at Collingwood from 2010 to 2012, claimed the silence of Buckley, Pendlebury, McGuire, Maxwell and Ball - a former AFL Players Association president - about Lumumba was disappointing.

"Scott Pendlebury, this is your moment to lead, brother," McNamara tweeted.

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"The last time I saw you, I gave you two leadership books.

"After your 400+ games, you will be the next CFC coach. In my eyes, your culture starts now - let's go!"

Lumumba has conducted numerous interviews and has been regularly posting on social media since the report's release, saying he feels vindicated by the findings of the investigation.

He first raised the alarm on concerns about racism at Collingwood in 2013.

Lumumba claims he experienced a culture of racism, which included being nicknamed "chimp" during his 10 seasons at the club.

As well as McNamara, former Collingwood players Andrew Krakouer, Chris Egan, Chris Dawes and Brent Macaffer have also publicly supported Lumumba.

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