Cape Town - Gary Kirsten has called Graeme Smith the "greatest captain ever" in Test cricket following Smith's retirement from the international game.Smith, 33, made this shock announcement on Monday during the last Test against Australia at Newlands. Australia went on to win by 245 runs to claim a 2-1 series victory.For Smith it brought an end a career of 117 Tests, and 107 as captain of the Proteas.He scored 9 265 runs, 27 tons and 38 half-centuries at an average of just under 49 with a highest score of 277 against England in Birmingham in 2003.And Kirsten, who played his final four Test series under a 22-year-old Smith before coaching him in later years, said Smith is likely the best Test skipper ever in the history of the game."Is he the greatest captain ever in Test match cricket? In my view he must be," Kirsten told the ESPNcricinfo website."I don't think anyone had led as long. We know that. He has taken South Africa to great heights. The kind of success he has had, the kind of success he has taken South African cricket to, I would argue that he is the best captain that has ever lived." South Africa's series loss was their first since 2009 and the Proteas still sit comfortably atop the ICC Test rankings.CLICK HERE for the full story on the ESPNcricinfo website.