Manchester United manager Louis van Gaal was delighted after his side's 3-0 win against Ipswich Town on Wednesday night.
The Red Devils move on to face Middlesbrough in the next round of the competition.
"The result was great," van Gaal said.
"We don't have injuries. I brought in players, I rotated players. Phil Jones has played a lot of minutes. So I'm a happy coach.
"[Martial?] It is not so difficult because he is a player who is very modest. He knows that he can score and he can score because of his fellow players.
"We made it for him two times very easy because we won the game and the gaps are existing. With his speed and composure, he can score. He did it against Liverpool and now again. We are happy but still we have to keep our feet on the ground.
"It [Middlesbrough] is a top club in the Championship. I don't know much about them.
"The scout shall analyse the opponents like he did with Ipswich. It is one of the top clubs so it is not so easy. I am very happy with the result. I am happy we are playing at home. We are travelling a lot so it is good to stay at home."