Poland beat Saudi Arabia in tight Group C encounter
Despite being second best for large parts of the game, Poland showed their class with clinical finishing and had goalkeeper Wojciech Szczesny to thank for a first-half penalty save.
Lewandowski pounced on a defensive lapse in concentration from Abdulelah Al-Malki to slide home his first-ever World Cup goal with eight minutes remaining to seal the win.
Saudi Arabia's match winner from their tie with Argentina, Salem Al-Dawsari, missed from the spot just before half time when presented with a chance to equalise, and they continued to be wasteful in the second half as they fell to defeat.
Poland were frustrated in the early stages, and picked up three yellow cards in the opening 20 minutes as they struggled to retain possession and cope with a lively Saudi side.
After an uneventful start overall though, the game burst into life at the end of the first half as Herve Renard's side were hit with the sucker punch, when Lewandowski squared for Zielinski who fired home into the roof of the net - Poland's only shot on target in the first half.
Saudi Arabia and Al-Dawsari were given a golden chance to level the tie in first half injury time though, when a clumsy challenge from Krystian Bielik saw Saleh Al-Shehri go down in the box, and after a VAR review, a penalty was given.
However, a poor spot kick was saved by Szczesny who then got up to make a miraculous save from Mohammed Al-Burayk on the rebound.
That was a contrast of emotions for Poland after their first game against Mexico, when they were the side who missed from the spot in their 0-0 draw.
Saudi Arabia continued to put pressure on Poland, as Al-Dawsari and Firas Al-Buraikan both went close, but Poland showed their threat on the counter as Lewandowski and Milik both hit the frame of the goal in the space of three minutes mid way through the second half.
The moment Lewandowski had been desperate for finally came with eight minutes remaining, as he was gifted a chance one-on-one after Al-Malki lost the ball on the edge of his own box, and he calmly slotted home, causing wild scenes on the Poland bench, as the Barcelona man was embraced by all his teammates.