South Korea s Kim Jin-su (top) fights for the ball with Cameroon s Bryan Mbeumo (front) during a friendly football match between South Korea and Cameroon in Seoul on September 27, 2022. AFP
The star striker headed the ball home after an initial shot from Kim Jin-su was deflected by goalkeeper Andre Onana in the 35th minute, and South Korea then hung on for the win in front of 59,000 fans at Seoul World Cup Stadium.
On Friday Son had netted a free kick in a 2-2 draw against Costa Rica.
South Korea and Cameroon, who are both Qatar-bound for the World Cup, had few serious chances at goal prior to Son's header.
Lee Jae-sung's diving attempt in the fifth minute forced a tough save from Onana, while Cameroon's Moumi Ngamaleu fired a right-footed shot over the net in the 26th.
Cameroon nearly levelled the score in the 43rd minute when Bryan Mbeumo's effort ricocheted off the body of defender Kwon Kyung-won and struck the crossbar.
South Korea had a chance to double their lead two minutes into the second half but Jeong Woo-yeong's header sailed over the net.
The Cameroonians' push for an equaliser proved futile, with Olivier Ntcham sending his left-footed shot right of the net in the 51st minute.
Goalkeeper Kim Seung-gyu helped the Koreans keep Cameroon at bay, proving up to the task when Martin Hongla tested him with a right-footed shot in the 70th.
Son came close to grabbing a brace with an 87th-minute free kick but the shot landed on top of the goal netting.
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