Hesson: Chance for Black Caps to step it up

New Zealand's Nathan McCullum celebrates with New Zealand's Martin Guptill after winning the second T20 International cricket match between South Africa and New Zealand.

On the eve of the three-game ODI series against South Africa, Mike Hesson has been stressing the continual search for improvement from his players.

The New Zealand coach has been impressed with the way some of the younger players, such as bowlers Ben Wheeler and recalled legspinner Ish Sodhi, have taken their opportunities, respectively in England recently and on the current trip to Zimbabwe and South Africa.

The first ODI at Centurion tonight offers a top opportunity, having squared the T20 series 1-1, to test themselves against a formidable, if slightly under-strength, South Africa.

No Faf du Plessis, troubled by a knee injury, star seamer Morne Morkel or JP Duminy, both for family reasons, means South Africa are not at their optimum. Then again New Zealand are without four senior players.

One player whose form might have Hesson quietly concerned is wicketkeeper Luke Ronchi.

Since his blistering unbeaten 170 off 99 balls against Sri Lanka at Dunedin on January 23, Ronchi's run return has been lean.

During the World Cup, he mustered only 73 runs at an average of 12; in the five-game series in England there were just 56 at 11.

Since the World Cup began, Ronchi has made 136 runs at 11.

They've come off only 118 deliveries, which amply illustrates his batting approach.He's a spectacular hitter and tidy gloveman, but he's well overdue to deliver with the bat.

Stand-in captain Kane Williamson and opening partner Martin Guptill are shaping as important figures for New Zealand. They have been able to produce good starts in both the T20 and ODI games on tour, and Williamson has mustered 274 runs across six innings in the two disciplines.

The key for New Zealand is making sure the middle order capitalise on the good early work. That's where the likes of Grant Elliott, Jimmy Neesham, Colin Munro and Ronchi come in.

South Africa's bowling, which includes star turns Dale Steyn and Vernon Philander, the lively newcomer Kagiso Rabada and clever legspinner Imran Tahir should provide a demanding test.

The mettle of younger players looking to make themselves permanent fixtures will be tested."We've just got to play well enough to put them under pressure and see how they respond," Hesson said of South Africa.

New Zealand have won just four ODIs out of 21 against South Africa in the republic.

That said, two of them were on the last visit in 2013, when the three-game rubber was won 2-1.

NZ v South Africa First ODI, Centurion, starts 10.30 tonight

New Zealand: (from): Kane Williamson (c), Martin Guptill, Tom Latham, George Worker, Grant Elliott, Colin Munro, James Neesham, Luke Ronchi, Nathan McCullum, Ish Sodhi, Doug Bracewell, Adam Milne, Ben Wheeler, Matt Henry, Mitch McClenaghan.

South Africa: (from) AB de Villiers (c), Hashim Amla, Rilee Rossouw, David Miller, Morne van Wyk, Farhaan Behardien, David Wiese, Vernon Philander, Aaron Phangiso, Dale Steyn, Kagiso Rabada, Kyle Abbott, Imran Tahir.* Ball by ball radio commentary on all three ODIs will be carried by Radio Sport, starting from 10.30pm.