The South Korean star completed our comeback from 2-0 down for a 2-2 draw at Manchester City on Saturday evening.
It was his seventh goal in the Premier League this term and right in front of delirious Spurs fans at the Etihad.
After four goals in his super September - where he made history by becoming the first Asian to win the Premier League's Player of the Month - Sonny volleyed home one of the goals of the season against Swansea and now, who knows how important this point might be?
Below: Sonny speaks to Spurs TV after the 2-2 draw
On as substitute for the start of the second half, Sonny swept home from 12 yards after Harry Kane's clever assist on 77 minutes.
Not quite ourselves at the Etihad, we were 2-0 down before Dele Alli headed home for 2-1 and we then lost Toby Alderweireld to injury - and Sonny had already come on for Kevin Wimmer, another central defender. So at 2-1 down and two centre-backs down, we managed to dig out a draw.
"It was so important after going 2-0 down to get back to 2-2," said Sonny. "We showed our character and mentality, which is so strong and I’m really happy for my team-mates.
"It was unbelievable (the feeling of scoring the equaliser) and the fans were unbelievable again, like always. Every time you score it’s a special moment but for me, we were 2-1 down and to draw 2-2 in Manchester City, this is a special memory for me."
'We're not robots'
Looking at the whole display, Sonny conceded we weren't at our best - making the result even more impressive from our point of view.
He added: "That’s football, sometimes it’s really difficult and we can’t play well every week. We always try, but we’re people, not robots. We try to get to the high level but sometimes it’s just not working.
"We came back and this is the answer."