Cape Town - Fellow golfer Ian Poulter has defended Open Championship winner Rory McIlroy after the Northern Irishman declined an autograph for a young fan.VIDEO: McIlroy says no to autographShortly after McIlroy won his first Open Championship at Royal Liverpool on Sunday, a young fan ran up to him asking for his autograph.McIlroy declined and walked on as stewards pulled the young fan away.McIlroy's snub sparked somewhat of an outrage among golf fans on Twitter on Sunday night, but Poulter was quick to defend his fellow professional.Poulter wrote on Twitter that McIlroy was not allowed to sign the autograph as he had not handed in his scorecard."Just to clear up the signature thing. We are asked not to sign autographs until we have officially handed in our scorecards. #RulesAreRules," Poulter wrote.It was not McIlroy's only incident with a fan during the final round, after earlier growing frustrated with a spectator whose noise interrupted his backswing at the 16th hole.He hit a near-perfect drive down the centre of the fairway - but took exception to one member of the crowd, pointing for the man to be ejected.Speaking out about the incident later, McIlroy said he had been consistently heckled by the offender throughout the day."He was giving me grief all day," McIlroy told the Daily Mail website. "I sort of put it up for the first 15 holes, and then he deliberately coughed on my downswing on the 16th tee."I still hit a great drive. But I heard it halfway down and I knew who it was. So I turned around and got him chucked out, thankfully."