Manchester United midfielder has sent a message to the Red Devils fans.
United beat Preston to set up the home clash with Arsenal for the weekend of March 7.
Herrera scored the equaliser after United had gone behind and says the support helped them through the tie.
He thanked the visiting fans and admits it’s important they push on in the cup.
“The support is always fantastic and it means a lot to us,” Herrera told MUTV.
“Today here in Preston’s stadium they were fantastic.
“They supported us at a tough moment and we are grateful for that.
“We won for them because after the first goal they pushed us for the victory.
The Spanish midfielder then went onto insist they can beat Arsenal at Old Trafford.
“We have to keep playing in this competition [and it will be] against Arsenal who are one of the best teams at the moment,” the midfielder added.
“But we are Manchester United and have a very good spirit and we showed it today. We have very good players and very good staff and we are going to improve.”