A 1-1 draw at home in gameweek 5 leaves Tottenham top of the group but just two points from bottom spot.
A game that showed the quality - and lack thereof for both teams - whilst also being a tight match that Spurs thought they had won before VAR cut the celebrations short.
Sporting opened the scoring half-way through the first half when former Tottenham youth star Marcus Edwards made Spurs regret their decision to let him leave.
The forward broke through the Tottenham midfield before shooting across Hugo Lloris into the bottom right hand corner.
The game then went back and forth with both sides trying to assert themselves on the game.
Spurs then broke through in the 80th minute when Sporting Lisbon keeper Antonio Adán misread a corner and let Rodrigo Bentancur head the ball into an open goal.
The home side had thought they had won the game when Emerson Royal headed the ball across goal to Harry Kane how put the ball in the net in the 95th minute.
However, after a long VAR review Kane was judged to be in an offside position and the goal was ruled out much to the frustration of Antonio Conte who was shown a straight red card by the referee after voicing his dismay at the decision.
Here are some of the main talking points from last night.
VAR Drama took the shine of an entertaining game
Despite a game that was full of entertaning football from both sides the only thing being discussed was Spurs disallowed last minute winner.
VAR has alwasy been a hotly debated topic between football fans with arguments for and against the technology highlighted since it's introduction.
With everything to play for in Group D a win for Tottenham would've seen them qualify for the knockout stages of the Champions League with a game left to go.
When Harry Kane put the ball past the Sporting keeper the home crowed celebrated what they thought was a much needed win for the north London side. Antonio Conte was jubilant hugging his coaching staff and players before a VAR check dampened the mood.
Two minutes later and both Sporting and Spurs fans alike holding their breath the goal was dissallowed. The result leaves Spurs needing at least a point in their last game to guarantee a spot in the round of 16.
The one that got away
Three points isn't the only thing that spurs missed out on based on last nights result. Former Spurs man Marcus Edwards came back to north London for the first time since his departure and showed Tottenham exactly why letting him go was a mistake.
After staring in the first leg and helping Sporting record a 2-0 win in the reverse fixture Edwards got the magical homecoming he deserved with a well worked solo goal to open the scoring.
With 10 goal involvements in 16 games across all competitions this season it's only a matter of time before Premier League clubs start sniffing around the 23yr old.
Conte's Spurs starting to show cracks
While it ended on a dissapointing note for Spurs the more dissapointing aspect will be the overall performance. With Spurs registering just two wins in their last eight games and conceding 10 goals Conte will be hoping to fix his defensive problems before this run of form continues any further.
With two important away games on the bouce against Bournemouth and Marseille, Conte will have to find a way to tinker with his side if he wants to keep Spurs in the top four and in the Champions League.
The Champions League is full of suprises
Every year there is talk about revamping or changing the structure of the Champions League with the European Super League the closest push so far.
However, Sporting Lisbon as well as host of other teams are proving this year that football doesn't get played on paper. Tottenham fans would've been licking their lips at the makeup of their group. But with one game to go Spurs have had the toughest path to qualification out of all the Premier League sides.
Sporting, Napoli, Club Brugge and Benfica have all given 'big sides' a headache and proven once against that the Champions League is the toughest club competition in world football.