Kewell, who is in Portugal receiving treatment for a groin injury, was not at London's High Court for the outcome.
The panel of six men and six women had been deliberating for just over six hours on whether the Match Of The Day pundit had defamed the 26-year-old Liverpool star in a July 2003 Sunday Telegraph column about his transfer from Leeds.
After hearing that they could not reach a decision on which at least 10 of them were agreed, Mr Justice Eady said: "The only step I can take is to discharge you from giving a verdict in this case."
Lineker joked outside court: "It looks like a replay. I can't say anything else because I don't know what is going to happen."