The South Korean was dismissed in the second half of Sunday’s 2-0 loss to Chelsea when VAR showed he kicked out at Rudiger in retaliation to being fouled.
Referee Anthony Taylor did not penalise Son, but VAR official Paul Tierney decided differently and advised Taylor to issue a red card.
Spurs have appealed against the decision, which led to the alleged racist abuse of the Chelsea defender, and are waiting to hear from the Football Association whether their player must serve a three-match ban.
But Mourinho, who sarcastically wished Rudiger well in his recovery from “broken ribs” after the game, says the German’s over-the-top reaction should be in focus.
“I hope the Premier League is still the Premier League and will always be the Premier League and I think the focus should be on Antonio Rudiger and not on Son,” Mourinho said.
“I’m not speaking about the racism incident, this is another thing. I am speaking about that incident, the red card.
“In the Premier League I love there is no space also for what Rudiger did. Stand up and play man. This is the Premier League.
“In some countries, especially now Latin cultures, you go to Latin America, Portugal, Spain, Italy and that happens, it is a cultural thing, but not in the Premier League, and the moment we try to punish the reaction of some player, insignificant reaction, but you try to punish and you let it go the other one, it is because then you become part of it (complicit).
“That’s why I was trying to joke and making a bit of fun about it.
“Come on, do you think Rudiger plays the next game or do you think he’s injured? I think he plays.
“And we speak about Son and don’t speak about him.”
Nevertheless, it is Son’s third red card of 2019 for a petulant act as he was sent off for pushing Jefferson Lerma at Bournemouth last season, then for a tackle on Everton’s Andre Gomes in November that broke the midfielder’s ankle.
Spurs also appealed against both dismissals, winning the latter.
Mourinho does not think Son has a temper problem, however, and insisted he was in control against Rudiger.
“A tiny reaction is an emotional reaction but is still an emotional reaction with control,” the Portuguese said.
“I don’t think it is different, what happened with (Mateo) Kovacic and Dele (Alli) (both players booked for grappling), with what happened with Son and Rudiger.
“For me the insignificant is insignificant. To send somebody home and to stop him doing his work and be on the pitch is not about insignificant, it is about significant.
“If you do an accumulation of insignificance then is when you arrive at the accumulation of yellow cards and you have two yellow cards for insignificant fouls you go out.
“But when you do in the game one insignificant foul that is not a red card, that is a yellow card.”
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