Jordan Ayew's late winner put Crystal Palace into the FA Cup fourth round as they finally broke down a resolute Grimsby.
The Ghanaian came off the bench to spare his side the embarrassment of failing to score against a side three divisions below them and who had played 87 minutes with 10 men after left-back Andrew Fox was sent off.
Palace had 30 attempts on goal, only to be repelled by Grimsby's fine defence.
But with less than four minutes to go, Ayew won a free-kick which was curled into the area by Schlupp, and his fellow Ghanaian was there to head past McKeown and ensure the Eagles’ place in round four.
Jordan has now scored two goals in two games for Palace this week after going 14 matches without a goal.
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