Pelembe will be with the PSL Champions for a year after he helped them win their first Absa Premiership title.
Clever Boys CEO Jose Ferreira says the duo will be retained.
“We have exercised the option, and we keep Knox this coming season,” Ferreira tells KickOff.com
“Pelembe has signed for one year with an option,” he adds.
The Mozambican initially joined the Students in July 2015 from the Downs.
Wits have already signed midfielder Daylon Claasen, who joined the club as a free agent.
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