Bukayo Saka restored Arsenal’s lead with a second-half penalty, but Son had the last word with his second goal as these bitter rivals both extended their unbeaten starts to the Premier League season.
Tottenham sit in fourth place, above fifth-placed Arsenal on goal difference, after a hard-fought clash offered more evidence that Postecoglou has revived a club in turmoil when he arrived from Celtic in the close-season.
Although Tottenham have now won just one of their last 31 league trips to Arsenal and remain without a victory on enemy territory since 2010, there was much to admire from Postecoglou’s team.
Not only did they show impressive character to twice hit back from Arsenal’s goals, but they did it with the kind of eye-catching play that was so rarely seen during Antonio Conte’s reign.
Tottenham have scored at least twice in all six league games under Postecoglou despite the close-season departure of the club’s record goalscorer Harry Kane to Bayern Munich.
For Arsenal, it was a frustrating afternoon as they lost ground on leaders Manchester City, who stand four points above them in the title race.
Arsenal tested Tottenham’s mettle in a blistering start as Saka scooped a pinpoint cross to the far post, where Gabriel Jesus’ half-volley drew a fine save from Guglielmo Vicario.
If that was a well-crafted chance, Arsenal’s second opportunity came gift-wrapped by Tottenham defender Destiny Udogie.
Udogie’s woeful backpass was intercepted by Eddie Nketiah for a fierce strike that Vicario repelled at his near post.