South Africa survived a major scare from Nepal in scrambling a nerve-jangling one-run victory in their final Group D match of the T20 World Cup at the Arnos Vale Stadium in St Vincent on Friday.

Needing eight runs off the final over in pursuit of a modest target of 116 for a stunning upset win, the Nepalese fell agonisingly short at 114 for seven with Gulshan Jha run out off the final ball as he attempted a single off Ottneil Baartman to force a super over.

"Very grateful to have got the win, we were not near our best tonight," relieved South Africa captain Aiden Markram said afterwards.

"Reflecting back on the game over the next few days, there will be a lot of learnings for us.

"First and foremost, the way Nepal bowled it made it really tough for us. They put us under a lot of pressure."

After leg-break bowler Kushal Bhurtel (4 for 19) and off-spinner Dipendra Singh Airee (3 for 21) limited the Proteas to 115 for seven batting first, Aasif Sheikh (42) and Anil Sah (27) featured in a 50-run third-wicket partnership which pulled the Nepalese within touching distance of a result which would have kept their hopes alive of getting to the Super Eight phase of the tournament.

Dropped on one to a caught-and-bowled chance by pacer Kagiso Rabada in just the second over of the innings, opening batsman Sheikh saw off the first threat of Tabraiz Shamsi only for the left-arm wrist-spinner to return for a final over in the 18th over of the innings to claim both Sah and Sheikh in finishing with the excellent figures of four for 19.

Anrich Nortje then bowled Kushal Malla in the 19th over to tilt the balance South Africa's way and they just managed to hang on for the win amid unbearable tension.

Sandeep Lamichhane, denied a visa to enter the United States which kept him out of the first two matches, went wicketless through four overs of South Africa's innings but his mere presence seemed to lift his teammates after their captain, Rohit Paudel, won an important toss and put the Proteas in.

Already assured of a place in the Super Eight phase of the tournament and fully expecting to close out the group campaign with a fourth win in as many matches, none of the South African top-order were able to get on top of the bowling, although opener Reeza Hendricks managed to give the innings some sort of stability with a topscore of 43 off 49 balls (five fours, one six).

Nepal's bowlers were in their element throughout the innings with only a late effort by Tristan Stubbs (27 not out off 18 balls) causing them some concern before Bhurtel closed off the innings with the wickets of Marco Jansen and Kagiso Rabada off successive balls.

"I think I am very proud of the unit, especially the way we bowled and batted," Nepal captain Paudel said.

"I thought we fought very good. If we get more exposure to games like this, we will be on the other side."