The Dolphins looked likely to win the MTN40 semifinal first leg in Bloemfontein until a seventh-wicket partnership between Knights pair Obus Pienaar (31) and Johan van der Wath (29) swung the game in favour of the home team.
Pienaar and Van der Wath scored 54 off only 25 balls, taking the Knights past the Dolphins' total of 226 for a four-wicket victory.
Pienaar faced only 20 deliveries in his innings, hitting four fours and a six. Van der Wath, who won the man of the match award for his efforts, faced a mere 14 deliveries and struck three sixes and a four.
He hit two of his sixes off Englishman Ravi Bopara before Bopara left the field with cramp.
The Dolphins seemed in control of defending their total thanks to a tight spell of fast bowling by Kyle Abbott. He took two wickets for nine runs in his first spell of five overs.
But he too fell victim to the lower-order attack, conceding 25 runs from the 38th over.
The Knights got off to a horrendous start, losing opening batsman Morne van Wyk to the first ball of the innings, bowled by Jon Kent, and then Rilee Rossouw for only one.
At 5/2, the Knights had a fight on their hands until a fourth-wicket partnership of 109 between Reeza Hendricks and Dean Elgar brought them back into the game.
The second leg of the semifinal will be played on Friday in Durban.
In the other semifinal, the Titans beat the Lions by three wickets at Centurion on Friday night. These teams will meet in the second leg at the Wanderers on Wednesday. - Sports staff
Scores in brief: Knights bt Dolphins by four wickets. Dolphins 226/7 (Ravi Bopara 64; Jandre Coetzee 2/33). Knights 227/6 (Reeza Hendricks 64, Dean Elgar 58; Kyle Abbott 2/37).
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