Zambia coach Herve Renard has hailed his team for the "efficient” way they sailed through to the semi-finals of the Africa Cup of Nations.The Chipolopolo beat Sudan 3-0 in Bata on Saturday."I don’t say we played well, but I say we did well,” the French coach told BBC Sport after the game."We were efficient today. Some people might have thought it was easy - it wasn’t.”The match was played out in an almost empty stadium in Bata and Renard admitted that this made it harder for his team to raise their game."I told the players there are millions of Zambians [watching on television] and people around Africa, Europe and the world,” Renard said.