After an indifferent start to the World Cup, Steyn marked his 100th one-day international with 2-39 in the 201-run mauling of Ireland at the Manuka Oval on Tuesday.
Bowling with pace and venom, Steyn sent back opener Paul Stirling for nine and then had danger man Ed Joyce picked up for nought as the Proteas claimed their third win in four games.
However, Steyn still has relatively modest figures of 5-182 from the four games, having been dominated by India’s batsmen at the MCG, going for 1-55 in his team’s 130-run defeat.
By contrast, fellow fast bowler Morne Morkel has 9-174 from four games while the unheralded Kyle Abbott boasts 6-58 in two matches since he came in to replace the injured Vernon Philander.
“I’ve got no worries about Dale at all,” insisted de Villiers. “He’s going to win us a couple of crucial games in this tournament.
“He runs in with a lot of energy, intensity. He bowled with pace again against an Ireland team that it’s very easy to sort of sit back and go ‘I don’t really have to give it all my all here, we just have to relax; we’ve got 400 on the board’.
“He ran everything 140 (kph) plus. I believe he’s still in great form, and I know he’s going to win us a couple of games, it’s just a matter of time.”