Cape Town - Proteas cricket star Faf du Plessis has announced that he is engaged to girlfriend Imari Visser.Du Plessis, 28, announced the news on the social networking site, Twitter."In other news.....I'm engaged to @imarivisser.most romantic day of life!!!#shinebrightlikeadiamond," he tweeted.Cricket South Africa also wished the couple well after hearing of the news."Congratulations @faf1307 and @ImariVisser on your engagement!," CSA posted on their official Twitter page.Du Plessis played an instrumental role in helping the Proteas win the recent Test series in Australia. His 110 not out in the second Test in Adelaide helped South Africa pull off an unlikely draw which proved vital in the 1-0 series outcome.Du Plessis, who made his Test debut in that Adelaide draw, currently averages 146.50 after four Test innings.