The hosts impressed on the night and deserved the win, but Tottenham were below par and were caught napping twice late on and paid the price.
Here are the main takeaways from the match which saw Spurs lose their first game since April, a 0-1 defeat against Brighton.
Sporting Lisbon are a force to be reckoned with
After an emphatic 3-0 win against Eintracht Frankfurt in the opening group game of this season's Champions League, a 2-0 win against Spurs proves the quality Ruben Amorim's side has.
The Verde e Brancos were able to break well throughout the game, and took their chances late on to secure their first ever win against an English side in the Champions League.
They were able to wrap the game up quickly after taking the lead, hitting the visitors on the break just minutes after their opener in second half added time.
This could mean that Sporting may be a hard side to beat once they have the lead.
The result proved why many had praised Amorim for the style of football his team play, which was exciting and efficient, causing the Lilywhites all sorts of problems.
It is still early on in the group stage, but it was a vital win for Sporting, who will know they have every chance of reaching the knockout rounds after such a huge win.
Marcus Edwards has the potential to be a top player
Spurs fans will be all too familiar with the 23-year-old, who was a product of the club's academy, making his only appearance in a win against Gillingham in the Carabao Cup.
It is safe to say that he is now an entirely different player to the one that left Tottenham in 2019 amid concerns over his attitude.
On the night, Edwards was superb, driving at the heart of his former employer's defence, beating several players and forcing a great save from Hugo Lloris in one of the final actions of the first half.
Whilst he is clearly nowhere near the level of the Argentinian, Edwards' ability to entertain and create chances from nowhere was evident against Tottenham.
After seeing a display of such high calibre from him, perhaps it was enough to make Spurs regret selling him in the first place.
A loss had been coming for Tottenham
In truth, the Lilywhites have not produced many convincing victories at all this season, and whilst they remain unbeaten in the league, fans are becoming frustrated by the way the North London club are playing.
A dismal display in a defeat which saw the visitors let two goals in past the 90-minute mark certainly could act as a wakeup call.
There are only so many times a team can scrape past their opposition and claim a victory, which has often been the case for Conte's side this campaign, making the defeat long overdue for Spurs.
Conte's current team selections are not getting the most out of his side
On the opening day of the campaign, Tottenham were able to bounce back from going a goal down to win 4-1 against Southampton.
Having struggled to produce a win as comfortable as that since, it is perhaps slightly strange to see both players rarely included in the starting lineups since then.
Kulusevski has been dropped for Richarlison, who has admittedly had a fine start to life as a Spurs player, but with Heung-Min Son failing to score this season and the current front three struggling to link up as well as they were last term, something has to change.
It is a similar story at the other end of the pitch.
Whilst Ivan Perisic has impressed after replacing Sessegnon, the offensive movement is nowhere near as free flowing as last campaign, and the Englishman's bursts down the left wing have been missed.
On the right-hand side, Emerson Royal has started every game so far for Spurs this season, whilst Matt Doherty, who was in the best form of his Tottenham career before being injured late on last campaign, has only featured once.
Tottenham have also not made much use of their new signings, having brought seven new players into the squad in the summer.
Conte has access to plenty of options, yet his side have looked bereft of creativity or energy in recent weeks.
Perhaps the defeat, and the nature of it, will prompt Conte to make alterations to the team against Leicester on Saturday to freshen up a Spurs side which looks to be in dire need of some changes.