The 21-year-old performed superbly as Rio Ferdinand's replacement in the Manchester United defence.
Matchwinning hero Wayne Rooney claimed Smalling deserved the man-of-the-match prize for the manner in which he subdued Carlos Tevez and Sir Alex Ferguson also heaped praise on the youngster afterwards.
Going nowhere: Chris Smalling shackled Carlos Tevez on just his fourth start
It was a marvellous feat considering he was making only his fourth Premier League start since a ?7million summer move from Fulham.
And he loved every minute.
'I knew I was going to be playing earlier in the week so I had a lot of time to prepare,' he said.
'People have been telling me just what a massive game this is.
'Once I got my first touch it was a case of enjoying it and playing like any other game.
'It was a great occasion and I really enjoyed myself. To win it and play my part is a real joy.'
Considering he was at Maidstone three years ago, Smalling has grown up pretty quickly.
And the Londoner is starting to get used to the demands of being a United player.
'We all saw the table before the game and knew how crucial this game was,' he said.
'It had been emphasised to us all week, every time we stepped on the training field.
'In the end, we got our just desserts. Their goal was pretty jammy and it would have been a travesty if they had taken anything out of that game.'
Take a bow: Wayne Rooney's wonder strike won the Manchester derby for United
That Manchester City did not collect a point from their Old Trafford visit was down to the magnificence of Rooney's overhead kick, a goal Smalling is happy to watch over and over.
'We saw it on TV in the dressing room,' he said.
'It has come right out of the middle of his foot and flew into the top corner. There is no better way to win the game. Wazza worked tirelessly all game. It was a fabulous occasion.'
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