After netting twice on his home debut against Qarabag on Thursday, the South Korean international was back on the scoresheet again, converting a swift breakaway in the 68th minute as we finally pierced the Palace defence having dominated possession and chances created.
And while Hugo Lloris pulled off a world-class save to deny Bakary Sako in the second period, we were solid in defence and kept a third straight clean sheet in the Premier League as we recorded a third win in eight days in all competitions.
While it was much-changed side from the team that defeated Qarabag in the Europa League, there was just the one change in terms of our side which beat Sunderland last weekend, with Erik Lamela coming in for the injured Ryan Mason.
We were quickly onto the front foot and saw our first opening after just three minutes. Son cut onto his right foot and hit a 25-yard drive which deflected off Damien Delaney’s head for a corner. Lamela’s set-piece fell kindly to Harry Kane unmarked but he headed well over.
We were seeing plenty of the ball in the opening exchanges, Son having another shot blocked while Dele Alli just failed to find the South Korean with a threaded pass inside the area, and on 17 minutes a lovely turn from Lamela 25 yards out gave him space to fire in a left-foot shot which Alex McCarthy saved diving low to his left.
The first real threat from Palace came on 21 minutes when Yannick Bolasie slipped a pass in to Bakary Sako down the left channel of the area, he fizzed in a dangerous low cross but Jan Vertonghen cleared for a corner. The set-piece was hit deep, Pape Souare heading goalwards and Brede Hangeland swivelled to fire in a shot but it was straight at Lloris.
There was a lovely ebb and flow to the contest and almost immediately at the other end, McCarthy was there again to deny Lamela.
Bolasie wriggled through three challenges but his 20-yard shot flicked off Vertonghen for a corner which came to nothing on 25 minutes, another Son shot deflected off James McArthur to safety and Ben Davies attempted a long-ranger which went well over.
We were almost ahead on 32 minutes, Nacer Chadli laying the ball into the path of Alli 25-yards out. McCarthy stretched to save his effort, Kane this time did get on the rebound but from a tight angle could only fire right across the face of goal.
There were chances coming at both ends by this stage, the always dangerous Bolasie cutting inside Kyle Walker and attempting to curl a shot towards the far post but it was comfortable for Lloris. And after the Palace winger was upended 25 yards from goal by Davies, Sako stepped up and hit a fierce free-kick which Lloris punched clear.
On the stroke of half-time the visitors carved out their best chance after a spell of pressure, Yohan Cabaye drilling a shot from the right-hand side of the area which evaded the dive of Lloris but crashed off the far post - and it was goalless at the break.
The second period began in the same fashion as the first, with us on the offensive and when Alli was bundled over right on the edge of the area on 52 minutes, Lamela took responsibility for the free-kick. His left-foot effort got up and over the wall, but McCarthy was able to palm away for a corner.
We did have the ball in the back of the net on 58 minutes, Davies nodding home after excellent work from Lamela and Son, but Kane was adjudged to be offside in the build-up and it was disallowed.
It needed a superb save from Lloris to keep the scores level on 65 minutes when he produced a one-handed diving stop to tip Sako’s angled drive from 15 yards onto the far post. From the corner, Hangeland climbed highest to head the ball down and in the melee, substitute Fraizer Campbell blazed over.
There was a change to our personnel on 66 minutes when Christian Eriksen made a welcome return from injury, replacing Chadli, and he was quickly into the action to set up our opening goal two minutes later. Lamela blocked a Palace effort on the edge of our area and we were swiftly on the counter-attack, Eriksen surging forwards before laying into the path of Son. He advanced in on goal, confronted by Hangeland but he shifted the ball onto his left foot and fired through McCarthy’s legs into the back of the net.
And it was the Dane at the heart of another breakaway on 77 minutes, flicking a pass out wide to Alli who burst into the area before curling a shot wide of the far post.
Another substitution was made on 79 minutes as Clinton Njie came on for his Premier League debut, replacing Son, who received his second standing ovation in four days!
It was tense in the closing stages as Palace stepped up the pressure in search of an equaliser, Lloris having to be quickly and bravely off his line to clear at the feet of Campbell, while Toby Alderweireld did excellently to head away a dangerous cross as the visitors probed for a goal.
But despite some late possession and a few crosses into the box, we were never seriously threatened and held firm for a fine victory.
Spurs (4-2-3-1): Lloris, Walker, Vertonghen, Alderweireld, Davies, Dier, Alli, Lamela (Carroll 87), Son (Njie 79), Chadli (Eriksen 66), Kane. Substitutes (not used): Vorm, Trippier, Fazio, Townsend.
Palace (4-2-3-1): McCarthy, Kelly, Hangeland, Delaney, Souare, McArthur (Mutch 76), Cabaye, Zaha (Campbell 46), Puncheon, Sako (Bamford 84), Bolasie. Substitutes (not used) Hennessey, Mariappa, Lee, Ledley.
Goals: Spurs – Son 68.
Yellow cards: Spurs – Lamela; Palace – Kelly, Bolasie.
Referee: Michael Oliver.