"Tom Curran returned early from the Pakistan Super League and scans have shown he has suffered a stress fracture of the lumbar spine," Surrey, his county, said in a statement.
The club did not put a timeframe on Curran's return, saying: "Tom will be out for a period of time whilst he recovers and undergoes rehabilitation at Surrey."
ESPNcricinfo understands that he is considered a doubt for the start of the Blast on May 20, and may miss the competition altogether depending on his timeframe.
He was also recently retained by Oval Invincibles on a £100,000 contract in the Hundred, which starts on August 1.
Curran, who recently turned 28, has played 60 times for England across all formats but has slipped down the pecking order at international level. His most recent appearances in ODI and T20I cricket came in July 2021.
He has spent the first two months of the year playing overseas, first for Desert Vipers in the inaugural edition of the ILT20 and then for Islamabad United in the PSL.
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