Cape Town - Former SA batsman Daryl Cullinan says Proteas captain Graeme Smith brought a Steve Waugh-like mental strength to the team.Speaking to ESPN Cricinfo's website, Cullinan reserved high praise for Smith."He brought a belief and character into the Proteas team, he never shirked his responsibility, he loved the challenge, he was always up for it. "His presence and inspiration brought a Steve Waugh-like leadership to South African cricket," said Cullinan.Cullinan called Smith not only a great captain but "the greatest opening batsman of his generation"."I would have loved to play cricket with him," Cullinan said.Cullinan said Smith and Jacques Kallis' retirement, will leave South African cricket in a bit of a conundrum."These two brought so much in terms of leadership and experience to the team, but it's now (Hashim) Amla, (AB) de Villiers, and (Faf) du Plessis' time. They'll have to pick up where Smith and Kallis left off."Cullinan said he believed the weight of the captaincy had contributed to Smith's early retirement:"He took on a lot as a young player and I felt he never always got the support he deserved. There must have been an element of burnout with the burden so heavy on his shoulders," Cullinan said.Asked who he thought would replace Smith, Cullinan felt that it would be a "tall order" for AB de Villiers to carry the responsibility of being captain, wicketkeeper as well as South Africa's premier batsman in all forms of the game."There is a strong thought that du Plessis is the man to lead South Africa now," said Cullinan.