"[The manager] put me on and the thing he told me was to come in and try to score or give an assist, so I did what he was hoping because I delivered the cross," said the 22-year-old.
"When I got the ball from Ashley Cole my first impression was to put the ball in the box because the game was nearly done, and I was hoping that Didier or Anelka was in a good position to attack the cross. It was lucky that Riise put it in.
"It is a good advantage, but we have to make use of it to get to the final. Ninety minutes away from the final is a great place to be."
Chelsea entertain Manchester United this weekend and Kalou also told Chelsea's website: "Another big game, another big competition and we have to go for it again. It is exciting and when you play for a big team like Chelsea you hope every week to play this kind of game."