Son helped himself to two goals in today's early kick-off while Harry Kane made a welcome return from injury.
Heung-Min Son hit two goals, and nabbed an assist, as he helped Spurs to a 4-0 rout over Watford today, to put them momentarily within four points of Chelsea.
Dele Ali and Eric Dier were also on target, while Harry Kane made an appearance off the bench following an injury lay-off.
Mauricio Pochettino's side got off to a tentative start in today's early kick-off, allowing Watford to build attacks and threaten keeper Hugo Lloris.
But they soon took control of the tie and came close to breaking the deadlock just after 20 minutes when an incoming ball caught Vincent Janssen by surprise and he ended up helping the ball into the crossbar rather than into an empty net.
Janssen was presented with another opportunity moments later which again, he failed to convert when he couldn't get into position to get on the end of a pass across the face of goal.
Image: Mousa Dembele taking on the Watford defence
Dele Ali finally ended the home side's frustration and put his side in front just after the half-hour mark. Ali collected possession on the edge of the area and curled a superb strike past the helpless clutches of Heurelho Gomes.
Eric Dier doubled their lead shortly after, when he smashed a low shot off the surface and into the net. Watford had little relief against the relentlessness of the Spurs attack and before the half-hour mark, they were three goals down.
The superb Son picked up the ball in space and advanced a few yards before unleashing a beautiful shot that settled in the bottom corner of the Watford goals.
Watford's torture continued after the restart and Son made it 4-0 in the 54th minute - this time with a volley from close range.
Image: Dele Ali after scoring his side's first goal of the game.
Meanwhile, Harry Kane made a welcome return to the pitch on 60 minutes. The striker, who was previously sidelined with injury, made an instant impact with some incisive runs through the heart of the Watford defence.
Tottenham's fourth goal arrived when Kieran Trippier angled a superbly weighted cross into the Watford area, which Son sent riffling into the net with a volley and some promising movement up front.
The in-form forward went in pursuit of a deserved hat-trick, but two bizarre misses ensured he would finish the day with just a brace from play.
His first chance was provided by Kane, who slipped the ball into Son's path. And with just the keeper to beat, it should have been a routine finish, but his casual shot sailed wide.
A second opportunity at stealing a hat-trick was denied by the crossbar, when the South Korean drilled his shot from close range past Gomes, but an otherwise excellent shot was kept out by the woodwork.
Chelsea face Bournemouth in the 5.30pm kick-off, where they need a victory to hold off the challenge of Spurs at the top of the table.