The Pakistan Cricket Board has asked former South Africa coach Mickey Arthur to back up reported comments that he suspected a one-day international against Pakistan in 2007 was fixed.
Arthur, in an interview with South African website News24 last week, there were "strong suspicions" of match-fixing when Pakistan collapsed dramatically to lose the fifth and decisive ODI against South Africa in Lahore three years ago.
"There was a strong suspicion of match-fixing and it took some of the gloss off the series win," Arthur said according to News24.
The PCB said in a statement on Friday that it had "served a legal notice on Mickey Arthur asking him to share with PCB any evidence in this regard."
"If the evidence is not provided PCB and Pakistani players reserve the right to initiate legal proceedings against Micky Arthur including but not limited to seeking unqualified apology, retraction and damages," the statement said.
Former captain Shoaib Malik, who led Pakistan in the 2007 series, said Arthur's claims were ridiculous.
"I don't know why this has come up after all these years, what is he trying to achieve by this. He has made a ridiculous claim," Malik told reporters.