The South Korea international reacted angrily after a tussle, first with Ryan Fraser and then Jefferson Lerma.
Lerma’s initial challenge seemed innocuous but Son pushed the Cherries midfielder to the floor and was shown a straight red by referee Craig Pawson.
Spurs’ misery was compounded just two minutes into the second half when Juan Foyth became their second player to be shown a straight red after a reckless tackle on Jack Simpson.
The Argentina centre-back had only come on at half-time and did not even touch the ball before being given his marching orders.
Incredibly, Eric Dier was also lucky to still be on the pitch at the half-time break as he was shown a yellow after only 11 minutes and escaped another for a cynical foul on Josh King.
Spurs fans and neutral observers reacted furiously to both Son’s reaction and the dramatic way in which Lerma went down for the first red card of the afternoon.
“Stupid from Son but the state of Lerma what a weapon,” one said on Twitter.
Another agreed: “Stupid from son and embarrassing from the Bournemouth player going down holding [his] face.”
Another added: “Idiotic from Heung Min Son after fouling Fraser for nothing he is sent off by the ref.”
A fourth simply noted: “Heung Min Son you silly boy.”
Supporters were also angry at Dier for coming so close to being sent off.
“We are absolutely loosing the plot,” one fad said on Twitter.
“Imploding at the end of the season. Of all people to get sent off, Heung min Son and Dier is Lucky to be on the pitch and should have conceded a penalty too. My word!!!!!”
Foyth’s actions did not go unnoticed among Spurs supporters, who were furious with their young star.
“Majority of times I’ve watched Spurs, Juan Foyth has been a walking disaster. They need to bin him off ASAP,” a fan said on Twitter.
“What an awful tackle from Juan Foyth,” another agreed.