The third tranche of the trial against alleged match-fixer Eric Ding Si Yang started on Tuesday as intrigue over two of seven mobile phones seized from him upon arrest took centrestage.

A grey Nokia phone he had allegedly used to communicate with Lebanese referee Ali Sabbagh via 10 calls was not registered to Ding but to a foreign national, Chen Xiaochun. Prosecution witness and the case's lead investigation officer, Senior Special Investigator Jeffrey Tan, said: "The identity number reflected is a foreigner PIN number, we were unable to trace this person."

But SSI Tan said that the phone calls made using the Nokia phone corroborate with records in Mr Sabbagh's phone, as well as the referee's earlier statements recorded by the Corrupt Practices Investigation Bureau.

Meanwhile, the Line chat application in an iPhone bearing a SIM card registered to Ding contained messages between him and a Thai referee about another official who was identified as "Thanom". SSI Tan said: "The user of the phone is talking to some Thai referee, and it has connotations of match-fixing." Ding shook his head upon hearing this testimony, which also prompted a half-hour debate between parties on whether the messages should be admitted as evidence in court.

Ding, 31, is standing trial for bribing referee Ali Sabbagh, 34, and linesmen Abdallah Taleb, 37, and Ali Eid, 33, also from Lebanon, with prostitutes in return for fixing a match. If found guilty, he can be fined up to $100,000, and/or jailed up to five years.

Defence counsel Thong Chee Kun argued that there was absolutely "no relevance" in admitting the Line messages as evidence and it would be "prejudicial for his client". He said that the messages were being "read in context to suit their (the prosecution's) purposes", and there is no proof that they were sent by his client.

Deputy Public Prosecutor Asoka Markandu argued that while the messages did not specify any particular match, there was a "mention of a failure to give goals that caused discord between the accused and Thanom".

He sought to admit the evidence on the basis of the Evidence Act, which allows for "similar fact evidence". He added that the defence had first brought up "Thanom" during the cross-examination of Mr Sabbagh, insinuating that Ding is well-informed in the industry and was giving advice to Mr Sabbagh to stay away from "Thanom", who was a "big problem to his company".