Fulham were without top scorer Aleksandar Mitrovic as they claimed a 0-2 win at the Cardiff City Stadium to boost their hopes of an instant return to the Premier League.
Cardiff started the match on the front foot, with Fulham only starting to get into the game towards the end of the first half.
The first big chance of the game came from Leandro Bacuna, who shot from outside the box forcing a save from Rodak, only for Michael Hector to stop Robbie Glatzel in superb fashion, preventing him from poking in the rebound from close range.
Just three minutes later, Cardiff came close again, with Robbie Glatzel putting a shot from the penalty spot straight at the keeper.
Then five minutes into the second half, Fulham's first goal came through Josh Onomah, who held off Marlon Pack on the edge of the box, before getting round him and driving into the box, before twisting and turning through two players before finishing into the bottom left corner.
Cardiff had what was their last chance to level three minutes from full time, when the ball was played over to a free Sean moriison in the box, only for him to miscontrol and it fall straight into the hands of Rodak.
Before in injury time, Neeskens Kebano put a free kick into the top right corner to seal victory for the whites.
This result means that Fulham have a comfortable lead to take back to Craven Cottage, where they play the second leg of the tie on Thursday night.