Harry Kane's first-half penalty was one of several talking points as Tottenham Hotspur built a narrow first-leg lead over Chelsea in the Carabao Cup Semi-Final.
With the help of VAR, Kane won and converted a spot-kick just before the half-hour mark - a goal which ultimately proved the difference on the night but has by no means put the tie to bed.
Both sides created good opportunities in what was often an end-to-end encounter, with the visitors hitting the woodwork on two occasions, leaving things fascinatingly poised going into the return meeting in two weeks' time.
Ahead of the game, Mauricio Pochettino opted to field an attacking line-up, with the likes of Christian Eriksen, Dele Alli, Heung-Min Son and Kane all involved from the start.
Chelsea boss Maurizio Sarri named eight changes from the side which faced Nottingham Forest in the FA Cup, with talisman Eden Hazard starting up front, youngster Callum Hudson-Odoi keeping his place, and Willian returning on the wing.
The home side had claims for a foul turned down inside three minutes, as Son raced onto Alli's excellent ball over the top and went down under challenge from Andreas Christiensen on the edge of the area.
Just 90 seconds later, Spurs were on the attack again, with Kane almost diverting Kieran Tripper's cross home with a superb acrobatic effort from inside the box.
Chelsea, meanwhile, were looking equally threatening on the break, and Hudson-Odoi got his first shot of the evening away on six minutes, picking up the ball on the right and forcing a low save from Paulo Gazzaniga.
The Spurs man was called into action again mid-way through the first half, when Hazard found space to turn in a dangerous position for the first time, with the goalkeeper well placed to deny the Belgian international.
Then came the big talking point of the half and, indeed, the match, as Kane raced through on goal and was brought down by Kepa, only for the referee to bring play back for offside, as signalled by the linesman.
After the use of VAR, Kane was adjudged to have been onside, meaning he had in fact earned Tottenham a penalty, which he slotted away emphatically to put Spurs ahead.
It was a goal which brought about a bit more purpose from the visitors, and they were inches away from levelling the scores through an unlikely source with half-time approaching, as N'Golo Kante got across a defender to meet Marcos Alonso's cross, but saw his effort hit the post and go behind.
They went even closer in added time, too, this time through the lively Hudson-Odoi, whose cross deflected off Danny Rose and looped up into the air. Gazzaniga managed to tip the ball onto the woodwork again, maintaining Spurs' narrow lead.
The second period began in the same manner as the first, with chances at both ends. First, Kane tested Kepa with a powerful strike from range, before Kante asked the same of Gazzaniga with a similar effort.
Chelsea's next chance was to be a golden one, but again it came and went without a reward - Christiensen stabbing the ball wide from close range with the goal at his mercy following a corner flicked on at the near post.
With half an hour remaining, the visitors looked the more likely, and turned to Pedro from the bench. A break in play though seemed to break the Blues' momentum though, with Spurs starting to settle again.
With chances now few and far between, the visitors made further changes, with Mateo Kovacic and Olivier Giroud introduced for the final 15 and 10 minutes respectively.
Sarri's side did threaten once more with the clock ticking down, as Gazzaniga palmed Hazard's low cross back into the middle of the area, but Spurs eventually cleared the danger.
It would prove to be the last chance of note, as Spurs saw out a valuable but slender victory, which leaves this Carabao Cup Semi-Final tie firmly in the balance going into the second leg.
Tottenham: Gazzaniga, Trippier, Alderweireld, Sanchez, Rose, Winks (Skipp 89'), Sissoko, Eriksen (Llorente 90+1), Alli, Son (Lamela 78'), Kane.
Subs: Lloris, Walker-Peters, Foyth, Davies.
Booked: Winks, Sanchez, Lamela
Goals: Kane (pen 27')
Chelsea: Kepa, Azpilicueta, Christensen, Rudiger, Alonso, Kante, Jorginho, Barkley (Kovacic 75'), Hudson-Odoi (Giroud 79'), Hazard, Willian (Pedro 63').
Subs: Caballero, Zappacosta, Luiz, Ampadu.