The International Cricket Council is investigating footage from the second Test that could land South Africa captain Faf du Plessis in hot water.Footage emerged on Wednesday, a day after South Africa took an unassailable 2-0 lead in the ongoing series with a crushing win over Australia in Hobart, that showed du Plessis applying saliva to the ball at Bellerive with a lolly in his mouth.In what appears to be a tactic similar to those used by England during the 2005 Ashes series to enhance the ball`s ability to swing, the clip shows du Plessis - with a white lolly in his mouth - licking his finger before rubbing the Kookaburra.No action was taken against England 11 years ago, however law 42.3 of the MCC cricket laws states that a fielder may polish a ball, "provided that no artificial substance is used".Neither umpire at Bellerive reported du Plessis. It`s understood Cricket Australia has not lodged an official complaint and has no intention to.But the ICC has confirmed the matter is being reviewed in Dubai. The organisation has a five-day window following the end of a Test during which it can lay a charge."The ICC has been alerted to the footage and is currently reviewing the incident from the perspective of it being a possible breach of the ICC Code of Conduct," an ICC spokesperson told cricket.com.au.England captain Marcus Trescothick in 2009 admitted he used mints to help produce saliva which kept the ball newer for longer periods during the 2005 series against Australia.Trescothick noted in his autobiography that the tactic did not cause as much of an effect on Kookaburra balls as they did the English Dukes.Du Plessis was fined by the ICC for rubbing the ball on a trouser zipper during a 2013 Test against Pakistan, something he was sledged about during a heated 2014 Test series between Australia and South Africa.Match referee David Boon noted in 2013 he was satisfied du Plessis` actions were "not part of a deliberate and/or prolonged attempt to unfairly manipulate the condition of the ball".Du Plessis was cautioned by both umpires at the WACA earlier this month during the first Test regarding his fielders bouncing their returns to the keeper - a tactic intended to rough up one side of the ball and achieve reverse-swing.Du Plessis said last week that issue had been "blown out of proportion"."We were watching the first innings and they got the ball to reverse in the 25th over. I was quite impressed ... to say it was only for us is not true," he said.In 2014, Australia opener David Warner was fined 15 per cent of his match fee after he all but accused South Africa`s AB de Villiers of ball-tampering during the second Test in Port Elizabeth.Warner`s comments did not relate to the use of lollies or saliva, but rather allegations the South African wicketkeeper was roughing the ball up with his gloves.Australia coach Darren Lehmann admitted his side struggled to face the swinging ball after their first-innings total of 85 in Hobart, while they were also routed for 161 in the second innings to meekly lose by an innings and 80 runs and concede the series.Source: cricket.com.au