However, Pedro Porro's late curling effort - also excellently stopped by the keeper, led to Sporting breaking the deadlock. Pedro Goncalves' resulting corner was met by Paulinho's glance and the ball floated into the vacant far corner.
After that 90th minute goal, there was still time for Arthur Gomes to produce a fantastic solo run, allowing for the lead to be extended. Gomes was only introduced to the game after Paulinho's opener.
Here are the player ratings from Estádio José Alvalade:
Antonio Adan - 7.5/10
Had five saves to make. Not quite as difficult as those that his opposite number had, but unlike Lloris, a clean sheet for Adan. A very assured performance.
Goncalo Inacio - 8/10
Had plenty of work to do defensively. A combined 10 clearances, tackles, interceptions and blocks made. Also maintained a 90% pass completion rate. Deserved the clean sheet.
Sebastian Coates - 8/10
Only misplaced three of his 63 passes from the middle of the Sporting backline. A brilliant performance, shutting Kane and Son out of the game.
Matheus Reis - 7.5/10
The injury issues in the centre-back area forced Reis to move away from his natural wing-back position. Had a very good game, was particularly assured on the ball.
Pedro Porro - 7/10
Was often the deeper of the two wing-backs. Didn't have as much of an impact going forward, but still put in an impressive performance.
Nuno Santos - 8/10
A very good game from the wing-back. Being a natural winger, he is taking to a deeper role very well. As you would expect, very good on the ball and responsible out of possession.
Hidemasa Morita - 6.5/10
Decent game. Was well disciplined in the middle of the park. Had to take a yellow card, after a poor pass from the backline forced him into committing a foul.
Manuel Ugarte - 7.5/10
A couple of times where he gave the ball away a bit loosely, but was an important, physical presence throughout the 90 minutes. Completed a combined seven tackles and interceptions.
Francisco Trincao - 7/10
A good game. Was an important part of an active front three. Was an important contributor defensively, as well - winning five out of his seven ground duels.
Pedro Goncalves - 7/10
A fairly quiet night, up until the corner he put in for Paulinho's late opener - the delivery was perfect into the near post area. Only misplaced two passes all evening, but didn't quite have the attacking impact he is capable of producing.
Marcus Edwards - 7.5/10
Was a very bright presence. Had a huge chance to put Sporting ahead just before the break, which was excellently saved by Lloris. Caused the Tottenham backline a lot of issues with his fantastic dribbling.
Sotiris Alexandropoulos (71') - N/A
A steady presence in midfield, after his introduction. Was able to provide a bit more freshness over the already-booked Morita.
Paulinho (76') - 8/10
A brilliant flick-on from Goncalves' corner gave Sporting the late lead. It was his only attempt at goal, following his introduction and what a crucial one it was.
Ricardo Esgaio (92') - N/A
Arthur Gomes (92') - 8/10
An incredible solo run to extend the lead, just moments after his very late introduction, following Paulinho's goal. Gomes picked up the ball from deep and took on successfully took on several defenders, before finding himself just in front of Lloris and producing a cool finish, to conclude the game.
Hugo Lloris - 8/10
Good save after Goncalves' low effort in the early stages of the game. An even better stop to keep out Edwards' shot from point blank range, just before the break. Finally, a great leap to deny Porro, late on - the resulting corner led to the opening goal.
Cristian Romero - 6/10
Was good with the ball at his feet - maintained a 93% pass completion rate. Not had to complete many defensive actions. Like the rest of the backline, was troubled by Sporting's front three.
Eric Dier - 6.5/10
Had the most defensive work to do, out of the Tottenham backline. Eight combined clearances, tackles and interceptions. Completed seven out of nine attempted long balls.
Ben Davies - 5.5/10
Advanced up the pitch fairly often, but was unable to create much for his team.
Emerson Royal - 6/10
Was particularly lively in the early stages of the second half - had a few chances to break the deadlock with efforts inside the keeper's box. Was beaten very easily by Gomes, for Sporting's second goal.
Ivan Perisic - 7/10
One of the most impressive performances from the visitors. Had plenty of work to do in and out of possession. Was a good outlet out wide for his team and was able to give Porro some trouble.
Pierre-Emile Hojbjerg - 6/10
Was a solid presence in the middle, but unable to have a serious impact and was fairly passive throughout his 90 minutes.
Rodrigo Bentancur - 7/10
Won eight of his ten ground and aerial duels. Was the more active and impressive central midfielder for Tottenham. Found himself quite high up the pitch fairly often, as well.
Richarlison - 6.5/10
Not able to keep up his goalscoring form from last week. However, was lively and found himself in some good positions throughout the night. Sporting defended well to hold their line and keep him offside on a few occasions.
Heung-min Son - 5.5/10
Another fairly underwhelming performance. Not able to have a real involvement in any of the Tottenham attacking play. Struggling to find his form this season.
Harry Kane - 6.5/10
Linked up play fairly well, produced a few chances for Emerson with his great passing ability. A left foot strike on the break was a very rare opportunity that he had, himself.
Dejan Kulusevski (72') - N/A
Introduced a lot of energy into the game, after replacing Son. Looked like he would have been able to have an impact, had he had more time.