NAGPUR: West Indies beat South Africa by three wickets after a relatively close encounter to cement a place in semis of the World Twenty20.

Electing to field, the West Indies bowlers restricted South Africa to 122 for eight before they rode on batsman Marlon Samuels' 44 to achieve the target with two balls to spare.

The win saw West Indies stay at the top of the Group One table with three wins from as many matches while South Africa's chances of advancing dimmed after two losses.

“We came here to win this match and qualify, and we've done that, so we're really happy,” Sammy said after his side's victory at Nagpur's Vidarbha Cricket Association Stadium on Friday.

The skipper admitted he was feeling “butterflies” as the Windies made hard work of it towards the end, going into the last over requiring nine runs to win.

Carlos Brathwaite hit a massive six before precocious fast bowler Kagiso Rabada bowled a wide.

Brathwaite then grabbed a quick run before Denesh Ramdin carried the Windies over the line with a single.

Marlon Samuels had earlier made 44 as the 2012 winners appeared to be heading for a comfortable victory, only for Imran Tahir to take two wickets in the 17th over and ensure a nervous finish.

It was South Africa's second defeat of the tournament and means England can secure a berth in the semis at their expense with a win against Sri Lanka on Saturday.

Bowling first, Chris Gayle grabbed two wickets as the West Indies restricted South Africa to 122/8 in their crunch World Twenty20 match.

Left-hander Quinton de Kock top-scored for the Proteas with 47 while David Wiese, batting at number seven, notched 28 after South Africa's top-order fell like a pack of cards.

The South Africans, who can ill afford to lose the match, got off to the worst possible start when opener Hashim Amla was run out for one on just the third ball of the innings.

Captain Faf du Plessis came in and didn't last long, scoring nine off seven balls before being caught by Sulieman Benn off paceman Andre Russell.

It quickly got worse for the Proteas when Gayle, who has barely turned his arm over in recent years, grabbed the wicket of Rilee Rossouw.

The left-handed batsman sliced a top-edge straight to Russell, who had all the time in the world to comfortably take the catch, walking for nought off two balls.

Rossouw's dismissal, which the dreadlocked Gayle celebrated with a little jig, left South Africa reeling on 20 for three after three overs.

South Africa needed AB de Villiers to put a big score on the board but the classy stroke-player could only manage 10 before being cleaned up by Dwayne Bravo.

The medium-pacer emulated Gayle's celebration, which is a dance from Bravo's new single called “Champion”.

David Miller then came in but lasted only four balls. Off-spinner Gayle, who's known more for his exploits with the bat rather than the ball, bowled Miller beautifully as South Africa struggled on 47 for five.

At the half-way stage of their innings the Proteas were on 57 for five. De Kock reached 47 in the 16th over before being bowled by Russell.

South Africa reached three figures in the 17th as Wiese did his best to get runs on the board before being caught by captain Darren Sammy off Russell.

Chris Morris made 16 as South Africa set the Windies a target of 123.