The 33-year-old had retired from international cricket earlier this month.
"Suresh Raina has returned to India for personal reasons and will be unavailable for the remainder of the IPL season. Chennai Super Kings offers complete support to Suresh and his family during this time," CSK tweeted CEO Kasi Viswanathan's statement.
CSK's quarantine period in Dubai has already been extended till September 1.
"Suresh's absence will be a big blow for the CSK and also, he is one of the biggest draws in IPL. But in these times, if any player doesn't feel 100 per cent and has some other pressing priorities, any team respects that and CSK is no different," a senior IPL official privy to development in CSK camp told PTI on conditions of anonymity.
While it couldn't be officially confirmed but speculation was rife that a family tragedy coupled by spike in COVID-19 cases in the team might have disturbed the former India left-hander who retired on August 15 alongside his skipper Mahendra Singh Dhoni.
While it is understood that the tournament is not under threat as of now but one franchise becoming a "COVID-19 hotspot" is slowly becoming an issue for other teams as well as the BCCI.
"If there are 13 cases from only one franchise then it is an issue for sure for everyone. The biggest aspect will be whether foreign cricketers will now start being panicky as they are more touchy about these issues," an official said.
"We need to keep a tab on players' mental health," he added.
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