On the back of two defeats and eight goals conceded in the competition so far, PSG really needed to find some form against the Europa League champions, but it looked like they were on course for another loss early on, with Atletico creating goalscoring opportunities with ease. However, having rode their luck defensively, Nkunku made the most of his opportunity to open the scoring after the returning Angel Di Maria had seen his effort blocked by Juanfran.
As he promised pre-match with PSG having played Arsenal just two days ago, PSG boss Thomas Tuchel rang the changes for the second half, making ten changes, but his youngsters really excelled, with 19-year-old Diaby doubling his side lead on 71 minutes.
Diego Simeone gave some of his youngsters their chance in the second half, and soon enough their tenacity was rewarded as Mollejo fired home from close range for Atletico, before the unfortunate Bernede diverted Borja's cross into his own net four minutes from time to level things up.
Nonetheless, up stepped Postolachi to finally earn PSG that victory they needed ahead of the start of their Ligue 1 campaign in fine style.
Christopher Nkunku of Paris Saint Germain reacts after scoring a goal during the International Champions Cup match between Arsenal and Paris Saint Germain at the National Stadium on July 28, 2018 in Singapore.
Image credit: Getty Images
Is this the season for PSG to utlise their talented youngsters? In the past, with immediate glory the priority for PSG's expectant owners, talented young players at PSG have been forced to leave to seek first-team opportunities - Kingsley Coman an example of such. However, with squad players such as Javier Pastore and Grzegorz Krychowiak departing, spots in the matchday squad have suddenly become attainable, and having put Atletico to the sword with some exhilarating attacking football in Singapore, the likes of Tim Weah and Diaby certainly showed they deserve to at least get their shot at the first team ahead of the domestic season.
MAN OF THE MATCH
Moussa Diaby (PSG). Having benefitted from some competitive action with France Under-19s recently, where he particularly impressed against England, Diaby took to the match in Singapore like a duck to water. He caused Atleti all kinds of problems with his pace and movement, thundered one brilliant strike against the crossbar, before drilling home a fine goal. One to watch, that's for sure.
Atletico: Adan 6, Juanfran 6, Toni Moya 7, Montero 6, Olabe 6, Thomas 7, Rodrigo 8, Mikel 6, Correa 5, Vietto 5, Gameiro 5... Subs: Joaquin 6, Mollejo 7, Borja Garces 6, Solano 6, 'Pinchi' 6, Isaac 6.
10' - SAVE! Big chance for Angel Correa after great work from Gameiro to set him up, but Kevin Trapp is out in a flash to block with his feet.
12' - CHANCE! Big chance for Gameiro this time. The France international raced clear, but took an age to get the shot away, before scooping it over the crossbar. Had to at least hit the target there.
32' - GOAL! PSG 1-0 Atletico. Clinical by Nkunku as he puts the French champions in front. A little sloppy at the back from Atleti as they fail to clear their lines, Di Maria's shot is blocked by Juanfran, but Nkunku is on hand to sweep home the rebound.
41' - OFF THE LINE! What a chance for Vietto. Trapp was beaten by the low shot after Rodri had picked out Vietto in space, but Ramane got back on the line to clear. Atleti have to make one of these chances count.
57' - NO PENALTY! Adan hesitates after a poor backpass in his direction takes an age to come down, Tim Weah is onto it in a flash, nicks the ball around Adan, goes down, but nothing is given!
63' - MISS! How have Atleti not scored there? Juanfran pulled it back for Jaoquin, who missed his kick, Vietto was on hand to convert the loose ball, but could not get the ball out of his feet and scuffed wide.
67' - CROSSBAR! My word, what a strike from Diaby out of nowhere, as his volley from full 20 yards cannons out off the crossbar.
71' - GOAL! PSG 2-0 Atletico. What a goal! What a player! Diaby nets to make it 2-0. Poor goalkeeping from Trapp as he comes out for a corner, but gets caught under the ball. He recovers well to save Mollejo's first effort, but cannot keep out the Atletico youngster's second.
76' - GOAL! PSG 2-1 Atletico. Game on as Mollejo converts from a corner to give his side fresh hope.Poor goalkeeping from Trapp as he comes out for a corner, but gets caught under the ball. He recovers well to save Mollejo's first effort, but cannot keep out the Atletico youngster's second.
86' - GOAL! PSG 2-2 Atletico. They have turned it around! So unlucky for Bernede, as he diverts the ball into his own net to gift Atleti the equaliser. Trapp seemed to be on the move very quickly, but he cannot take the blame after Bernede had inadvertently diverted the ball back towards his own goal as he tried to cut out Borja's cross
90+2' - GOAL! PSG 3-2 Atletico. What a way to win it! Postolachi with a stunner to steal it at the last! Postolachi's winner was right out the top drawer, as he turned on the edge of the box before curling a brilliant strike into the net.