JOIN USBoucher, who represented Royal Challengers Bangalore earlier, will be available for the Knight Riders ahead of their clash against Deccan Chargers on May 3.
"We are fortunate to have someone like Mark Boucher as Brad's replacement. He comes with a lot of experience and a terrific track record in all forms of the game," Knight Riders CEO and MD, Venky Mysore said.
Aussie wicketkeeper Haddin's IPL campaign was cut short after a fracture was detected in his finger. An MRI in Delhi on Thursday revealed that the injury he sustained during Australia's series in Bangladesh had not healed.
He will return home and undergo a surgery. "We are very disappointed that Brad (Haddin) will be leaving the squad and will not take further part in IPL IV. In a short period, Brad had made his presence felt both on and off the field," Mysore said.
The 33-year-old Australian cricketer was unavailable for KKR's first three outings as he was busy with national duty in Bangladesh.
After joining the side, Haddin scored 18 in his only appearance for the Knight Riders in their nine-wicket loss to Royal Challengers Bangalore in Kolkata.
An injury-prone Haddin, who had missed Australia's five-match ODI series against England last year due to an elbow injury, was roped in January's auction for USD 325,000.