The striker scored at the death to secure a point against Stoke City.
The Black Cats travelled to the Britannia on Saturday afternoon looking to pick up all three points in their fight against relegation.
Things did not go to plan though as a Marko Arnautovic strike threatened to see the Potters win the game and leave Sunderland in the relegation mire.
However, Defoe earned and then converted a late penalty, winning his side a vital point that could prove crucial as the survival race goes right down to the wire.
It was the striker’s 14th goal in the Premier League this year and Kaboul says he had no doubts that his teammate would score the penalty.
“No there was never any doubt,” he told safc.com. “He knows how important that penalty was, maybe it was one of the biggest of career up to now, and he was very relaxed.
“He concentrated and put it in the back of the net. You can trust him, and you can trust me on that.”
Sunderland must now hope that Defoe has more goals in his locker between now and the end of the season to ensure they can stay up.
He has been crucial to their hopes, with even manager Sam Allardyce admitting Sunderland would be relegated already if it had not been for his goal-scoring exploits.