Senegal became the first African team to win a match at the 2018 World Cup on Tuesday when they beat Poland 2-1, helped by two shocking errors in the European side's defence.
Poland defender Thiago Cionek stuck out a leg and deflected Idrissa Gueye's wayward shot into the net in the 37th minute before goalkeeper Wojciech Szczesny rushed unnecessarily out of his area and allowed M'Baye Niang to nip in and score into an empty net on the hour.
Grzegorz Krychowiak headed Poland's goal in the 86th minute.
The win took Senegal top of Group H with three points, along with Japan who also beat Colombia by the same score. Colombia and Poland are both without a point.
Egypt, Morocco, Nigeria and Tunisia all lost their opening games.
Poland's record scorer Robert Lewandowski got little change out of a well-drilled Senegal defence, led by Kalidou Koulibaly, and they sorely missed key defender Kamil Glik, still recovering from a training injury sustained two weeks ago.
The first half hour was a sorry affair strewn with misplaced passes from both sides and neither of the dangermen, Lewandowski and Senegal's Sadio Mane, seeing much of the ball.
The first shot on target produced the first goal as Senegal went ahead in the 38th minute.
Niang won a challenge with Lukasz Piszczek, burst down the left and found Mane who in turn slipped the ball to Gueye.
The midfielder's shot appeared to be going wide until the hapless Cionek stuck out a leg and deflected it past Szczesny.
Lewandowski sprang into life five minutes after halftime as he won possession, burst clear and was up-ended by Salif Sane. He took the free kick himself and although he managed Poland's first shot on target, it was saved by Khadim N'Diaye.
Poland appeared to be coming back into the game until the most embarrassing moment of the World Cup so far.
Krychowiak sent a long ball back from deep inside the Senegal half, Szczesny rushed out of his area to collect the pass but Niang stole in to score to Polish disbelief.
Krychowiak partially made amends with his goal but it was too late for the disappointing Poles.