The double Rugby World Cup winner, sidelined since the Boks' clash with Argentina in September 2024, considered stepping away as the injury affected his everyday life.
Erasmus said friends and Springbok management urged Malherbe to delay any decision, warning retirement would close the door on a future return.
"I had a meeting with him last year, and he was close to retiring. Not because he couldn't play anymore, but he was struggling with his back," Erasmus revealed.
"I think it was frustrating for him. So, some of us gave him advice, saying that he can't retire now and come back three years later and say, 'I don't want to be retired anymore'. A few guys did that; Os du Randt (former Bok prop) did it, but he wasn't very effective (when he came back). He was a very good team man."
Malherbe, now 35, has started 63 of his 76 Tests since debuting against Wales in 2013. Despite his time on the sidelines, Erasmus insists he remains part of South Africa's plans.
"We forget how good Frans really was for us only two years ago," said the Bok boss. "He is 100 percent on his way back. We don't want him to give up without having one more bite."
Malherbe has returned to Stormers training and attended the Springboks' first alignment camp in Cape Town, signaling a potential comeback ahead of a demanding 2026 schedule.
South Africa opens the year against the Barbarians on 20 June, faces England in the Nations Championship on 4 July, and takes on the All Blacks in a four-Test series, including one in Baltimore, USA.
Erasmus also noted other experienced players, like Willie le Roux, Vincent Koch, Bongi Mbonambi, Faf de Klerk, and Trevor Nyakane, remain in contention despite missing the first camp.
"I know the hearts of those boys. They can still show us they don't want it to finish this way, and we need that," he said.