The Belgian provided the assist – his 16th of the Premier League campaign – for Gabriel Jesus to snatch all three points at St Mary’s, ensuring the Blues completed a remarkable campaign with a record-breaking 100 points.
De Bruyne’s lofted pass to the Brazilian in injury time also handed the midfielder the inaugural Premier League Playmaker Award, as he jumped top of the standings – ahead of teammates Leroy Sane (15), David Silva (11) and Raheem Sterling (11).
It proved a fitting end to a truly exceptional season for City and for De Bruyne himself – and the Belgian could not have been more delighted.
“It was beautiful,” he smiled. “To have 100 points is unbelievable.
“We tried everything and we had to wait until the last second! It was a very emotional end to the season.
“We tried to attack. It was very difficult – they needed a point – but we were better in the second half and it was a beautiful way to end.
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“Throughout the season, we have made it difficult for our opponents and kept going until the end. Sometimes we’ve needed a little bit of luck or the right skill at the right time.
“We broke every record. I don’t think a lot of teams will reach 100 points.
“We tried to end the season on a good note. It’s so special. It’s never happened before in the Premier League and to have three digits of points is amazing.
“After we became Champions three or four weeks ago, it was the only thing to play for and it’s not that easy – the intensity goes down a little bit too much, you party a little too much and train less.
“The focus goes away a bit but we have been unbelievable.”
Reflecting on the goal – and his role in it – De Bruyne added: “I saw Gabriel Jesus making a run deep and I tried it (the long ball).
“It was all or nothing. When I played the ball, I knew it was behind (the Southampton defence). He controlled well and finished it the way he did. It was beautiful.
“It feels good (to have won the Playmaker Award). It means I have done a good job.
“I’m a creator and I try to create chances for my teammates. If they score, I get the assist and I look good!”
De Bruyne now hopes to take his sensational form into this summer’s World Cup – after a well-deserved rest, of course.
“We’ve got four or five days off and then we start preparation for the World Cup,” he continued.
“There is no rush – we have got enough time to prepare mentally and physically, although physically I am alright anyway.
“I’ll take my time and make sure I’m ready for the middle of June.
“The aim is always to do better and try to win it. There are ten or 15 teams who go there to win it and only one can so it’s very difficult.
“We’ll prepare ourselves to be in the best form possible and see what happens.”