New Zealand cricketer Jesse Ryder cannot remember any of the events that occurred on the night he was attacked in Christchurch.

The batsman was assaulted outside a bar in the early hours of Thursday morning, leaving the 28-year-old in an induced coma in hospital with a fractured skull.

"Unfortunately Mr Ryder has no recollection of what took place or the events leading up to the incident," Sky Sports News quotes detective senior sergeant Brian Archer as saying.

"Should Mr Ryder gain sufficient recollection as his recovery continues, then we may look to speak to him again, however there are no immediate plans to re-interview him."

A 20-year-old man and 37-year-old man are expected to appear in court on Thursday.