The talking is over. On Saturday, Britain\'s David Haye will finally climb into the ring for a unification bout with double champion Wladimir Klitschko that has been two years in the making. The pair were due to clash in 2009 in Gelsenkirchen, but a back injury forced Haye out and in the meantime he has won a world title of his own. In a sport renowned for trash-talking -- Muhammad Ali\'s coach Angelo Dundee once famously remarked that in boxing, silence was a crime -- Haye has taken the art of disrespecting an opponent to new lows with a tasteless campaign. \"Bitchko\", \"a fraud\" and \"the Ukrainian robot\" are just some of the insults he has hurled at Klitschko, who the Brit says he will visit in hospital in Hamburg on Sunday after promising to knock the Ukrainian out. Like him or loathe him, Haye\'s talent demands to be respected and he has both the power and fitness to take the IBF and WBO titles from Klitschko. He has announced himself as the self-styled saviour of the heavyweight division, but there is some truth in his arrogant boast. Before he won the WBA heavyweight title from the giant Nikolai Valuev in November 2009, the Klitschko brothers were picking off uninspiring title challengers seemingly at will, with neither Wladimir nor older brother Vitali genuinely tested. Vitali, the WBC heavyweight champion, will be the first in the queue to fight Haye if the brash Brit leaves Hamburg with all the belts on Sunday as the first British heavyweight since Lennox Lewis to hold more than one title. Both fighters suffered their last defeat in 2004 with fifth-round technical knock-outs: Haye to Carl Thompson as a cruiserweight at London\'s Wembley Arena, and Klitschko to Lamon Brewster in Nevada. Both fighters have matured and improved immensely since then and come to the ring at the peak of their condition. Haye has been loudly chasing the Klitschkos since stepping up from cruiserweight in 2008 and wanted a defining night against one of the brothers before retiring ahead of his 31st birthday. Having already seen the Brit pull out of one fight with him, Klitschko has said he will only believe Haye will fight when he sees the Londoner in the opposite corner. While Haye\'s power is undeniable, question marks appear over his defence and he has been put on the canvas by Thompson, Lolenga Mock, Jean-Marc Mormeck and Monte Barrett. But on all bar one of those occasion, Haye rose to secure victory and the fire in the Englishman\'s belly has been clear to see on each occasion. In his three losses -- to Brewster, Corrie Sanders in 2003 and Ross Puritty in 1998 -- Klitschko was beaten emphatically, but he is a different fighter today. In the defeats to Sanders and Brewster, crisp shots knocked him from his senses and it was a clear case of game over. That vulnerability has been either eradicated or hidden from sight for the last six years since Klitschko rose from the canvas three times and won comfortably on points against Nigeria\'s Samuel Peter in 2005. With a considerable height, weight and reach advantage, Klitschko starts as favourite, but Haye has the power to apply his considerable ability and beat Klitschko. Should he achieve his dream, he will write his name into boxing folklore and all the trash-talking will have served its purpose.