South Africa, a World Cup and pressure. Like a proper suit, they come as a three-piece set. That's why AB de Villiers fully expected to be under the pump in the opening match, albeit against Zimbabwe, and took heart from the way his team came through their first test in the tournament.

De Villiers praised the way South Africa fought through tough conditions early on in their innings, when the top order imploded against a disciplined Zimbabwe attack.

"The toss definitely played a big part in them getting ahead early on in the game," de Villiers said. "It was difficult to bat in the first 15 overs. It was slow and sticky, very Zimbabwe-like conditions and difficult to hit through the line. Zimbabwe don't have a lot of pace in their attack and they are very clever in the way they use the bowlers."

But it was only in the Zimbabwe chase that de Villiers really felt he was confronted with the possibility the game could go down to the wire and he had to demand more from his men. "At the first drinks break in the Zimbabwe innings I said to the guys, 'We are here in a tight game.' They were on target and we needed something to happen. We needed the pace to change."

Although de Villiers had made use of both JP Duminy and Farhaan Behardien, he only introduced his trump card, Imran Tahir, in the over before drinks and it was only after the interval that the legspinner began to look dangerous. Tahir had an appeal for lbw against Chamu Chibhabha turned down and proved difficult for the opener to pick. Chibhabha almost offered a return catch in the next over and then the over after that mistimed a slice over extra cover to the fielder on the boundary.

"Imran changed the pace for us," de Villiers said. "He formed some partnerships with the ball."

Still, de Villiers could not relax because Tahir's breakthrough brought together Zimbabwe's most experienced pair. Hamilton Masakadza and Brendan Taylor kept Zimbabwe in the hunt despite a mounting required run rate, which nevertheless could be overcome with just one big over. As South Africa showed when they were batting, wickets in hand at the end could make even 30 runs in an over possible.

"I felt pressure right throughout the game. You know you have to get wickets to win the game because if they have batsmen out there, they can get the runs," de Villiers said. "Those guys are not just out there batting for fun. You know you have to get breakthroughs all the time."

Tahir got the other major breakthrough as well when he had Masakadza caught at cover and that was when South Africa clawed back control. Even though Zimbabwe remained ahead of South Africa's equivalent score until the end of the 46th over, their actual challenge was stubbed out with about 15 overs to go and South Africa were guaranteed a comprehensive win.

That does not mean the favourites have nothing to worry about. De Villiers pointed to a "slow start" in the top order as an area to improve on but excused it this time, because of the conditions and the aggression shown by a middle order, which has solidified. Instead of concentrate on improvements, South Africa are looking forward to two days off after a win de Villiers said he was "very satisfied" with.

Firdose Moonda is ESPNcricinfo's South Africa correspondent