Martin Caceres shackled Son, harassing the South Korean winger any time he got the ball and sticking close to him to discourage others from passing his way.
This sets up Real Madrid final against Borussia Dortmund, who knocked out Paris Saint-Germain in the other semi-final.
IMAGES from the UEFA Champions League matches played on Wednesday
Atletico Madrid have recorded five COVID-19 positives, including manager Diego Simeone
Vinicius Jr scored a hat-trick in the first half as Real Madrid were crowned Spanish Super Cup champions
Karim Benzema and Vinicius Jr. scored in extra time as Real Madrid fought back to beat local rivals Atletico 3-1 and reach the Copa del Rey semi-finals.
Panama pulled off a shock 2-1 victory over the United States in a heated Group C encounter at the Copa America on Thursday.
Ghana captain Andre Ayew hit a feeble left-footed effort from the spot in the 21st minute which was saved by goalkeeper Sergio Rochet, who had been adjudged after a lengthy VAR review to have brought down Mohammed Kudus.
Real Madrid fans and players showed their support for Vinicius Jr who was subjected to racial abuse over the weekend.
La Liga leaders Real Madrid were held to a frustrating 1-1 draw at lowly city rivals Rayo Vallecano on Sunday as Joselu's early strike was cancelled out by Raul de Tomas' penalty, a result that could spice up the title race with surprise package Girona.
IMAGES from the FIFA World Cup Group H match played between Uruguay and South Korea at Education City Stadium in Al Rayyan, Qatar on Thursday
Vinicius Junior's second half tap-in steered Real Madrid to a 1-0 victory over Liverpool in the Champions League final on Saturday.
A summary of Tuesday's first leg quarter-final action in the UEFA Champions League.
IMAGES from the El Clasico match played at Estadio Santiago Bernabeu in Madrid on Sunday.
Real Madrid continued their march towards a 35th LaLiga title
Real Madrid midfielder Luka Modric came off the bench to net a stunning strike from the edge of the box late in the second half to secure a 1-0 home win over Sevilla on Sunday and stretch their lead at the top of La Liga to eight points.
Real Madrid did well to hold Atletico in regulation time and then win the match 4-1 in penalty shootouts.
With his calm guidance, Ancelotti gave Vinicius the confidence he needed to flourish.
Two goals from Luis Diaz and one from Mohamed Salah helped Liverpool stroll to a 3-0 victory at Manchester United.
Real will meet the winners of Thursday's semi between Barcelona and Atletico Madrid in Sunday's showpiece at the King Abdullah Sport City Stadium in Jeddah.
Vinicius Jr came off the bench to score once and set up another goal to steer champions Real Madrid to a 4-1 fightback victory over Espanyol.
La Liga leaders Real Madrid cruised to a 4-0 home win over relegation-threatened Celta Vigo on Sunday to restore their seven-point lead at the top of the table with a dominant display.
Real Madrid's Thibaut Courtois, Federico Valverde, Eduardo Camavinga and Vinicius Jr have tested positive for COVID-19.
Rodrygo and new recruit Jude Bellingham scored first-half goals to give Real Madrid a 2-0 win at Athletic Bilbao to kick off their LaLiga season.
Alvaro Morata scored a brace to help Atletico Madrid deliver a statement performance as they outclassed city rivals Real Madrid.
Lionel Messi's early goal earned Paris St Germain a 1-0 win at Olympique Lyonnais on Sunday as they opened a two-point lead at the top of Ligue 1.
Man City set to release skipper Gundogan and Mendy
Zinedine Zidane's side joined Atletico Madrid on 66 points and moved top of the table
Madrid's trip to San Sebastian was full of intrigue after Barca failed to beat Sevilla and the Catalan side's defender Gerard Pique said the title was now Madrid's for the taking.
Champions Real Madrid earned a 2-0 win in a feisty LaLiga encounter at Athletic Bilbao on Sunday to ensure they stayed in the hunt for the LaLiga title with leaders Barcelona.
A summary of the UEFA Champions League Group Stage action, on Wednesday.
Real Madrid overcame an early howler from Sergio Ramos to beat Real Sociedad 3-1 at home on an eventful Saturday at the Santiago Bernabeu, where Gareth Bale was loudly booed by his own supporters and Luka Modric returned to his very best form.
In a big blow to Real Madrid's title hopes, Real Betis held them to a goalless draw in their La Liga encounter on Sunday.
Manchester United's miserable season continued with a 3-2 home defeat by Galatasaray.
Real Madrid were made to toil by the 10 men of Athletic Bilbao but eventually won 3-1 on Tuesday thanks to two strikes from Karim Benzema to go level on points with La Liga leaders Real Sociedad.
Real Madrid through to next round, win 6-2 on aggregate, Liverpool ousted
Real Madrid defender Raphael Varane made up for the absence of Sergio Ramos by scoring one goal and making another to help his side to a hard-fought 3-0 win at Getafe. La Liga leaders Barcelona were held to a 2-2 draw at struggling Espanyol on Saturday as China striker Wu Lei came off the bench to grab a late equaliser in a pulsating city derby.
A round-up of Wednesday's action in the UEFA Champions League.
Holders Real Madrid breezed past Chelsea into the semi-finals of the Champions League with Rodrygo's double securing a 2-0 win at Stamford Bridge.
A 'winning culture' may be one of the most over used terms in modern football but Real Madrid and Carlo Ancelotti proved on Saturday, at Liverpool's expense, that there truly is meaning and value in the concept.