Sacramento, 30, was the assistant coach to Christophe Galtier in northern France. He initially joined Lille in January 2017 and worked under former coach Marcelo Bielsa, who was sacked later that year.
Santos has worked as goalkeeping coach at Lille since the summer of 2018.
Now 46, he was a goalkeeper on the books at Benfica in 2000 when Mourinho began his coaching career with the Lisbon giants.
Both men were close to Luis Campos, the Portuguese transfer guru who works as an advisor for Lille and is also close to Mourinho, who was appointed Spurs manager earlier on Wednesday.
Mourinho even attended a Lille game last season following his sacking by Manchester United.
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