Ngidi and Nortje, who made a sensational impression with his pace in a Twenty20 tournament early in the season, have both returned to action in recent weeks.
Johannesburg: Fast bowlers Lungi Ngidi and uncapped Anrich Nortje were named in a 14-man South African squad on Sunday for the first three of five one-day internationals against Sri Lanka.
Veteran batsman Hashim Amla was not included for the start of South Africa's last series before the Cricket World Cup in England from May to July – but selection convener Linda Zondi said Amla, 35, remained a senior player.
The series starts, at the Wanderers Stadium next Sunday.
"Those players who were in the squad against Pakistan (in January) but who have been left out this time have not been dropped. We need to use the first part of this series to examine all the options that are available to us," said Zondi. "We know, for example, what Hashim Amla has to offer us and he remains a senior member of our squad."
Also omitted is JP Duminy, who has not played since October because of a shoulder injury. Zondi said he hoped that Duminy, regarded as a key to South Africa's World Cup hopes because of his batting, fielding and off-spin bowling, would be fit for the final two matches against Sri Lanka.
Ngidi and Nortje, who made a sensational impression with his pace in a Twenty20 tournament early in the season, have both returned to action in recent weeks. Ngidi suffered a knee injury in Australia in November, while Nortje has been sidelined by an ankle problem.
Zondi said the selectors wanted to see what Nortje, 25, could offer. "Outright pace is not something that you can coach and he looks another exciting addition to our pace arsenal."
The squad includes only five players who were part of the Test squad beaten 2-0 in a Test series against Sri Lanka which ended on Saturday – captain Faf du Plessis, Quinton de Kock, Wiaan Mulder, Kagiso Rabada and Dale Steyn.
South Africa squad: Faf du Plessis (captain), Quinton de Kock (wkt), Reeza Hendricks, Imran Tahir, David Miller, Wiaan Mulder, Lungi Ngidi, Anrich Nortje, Andile Phehlukwayo, Dwaine Pretorius, Kagiso Rabada, Tabraiz Shamsi, Dale Steyn, Rassie van der Dussen.
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