The 21-year-old Perth-born midfielder, who has made four first-team appearances for the Villains this season, pens the deal just days after scoring a hat-trick in the Villa reserves incredible 10-1 win over Arsenal.

"I am really happy," Herd told AVTV. "I am just pleased to be here and pleased that I am going to be here for the next three-and-a-half years.

"When I got offered the contract it wasn't a difficult decision to make at all. A few of the other boys have done really well and have all signed contracts so it is nice to follow in their footsteps.

"All the boys stick together and are good mates on and off the pitch. We have all come through from the academy and it is nice when everyone is doing well together."

Herd added he was hopeful of going on to become a first-team regular for Villa in England's top flight.

"I am just going to try and get my head down and work hard in training and get into the team," he said.

"When you get that taste you want more - so hopefully I can get it. It just spurs you on."

Herd has been with Villa since he was 15 and he paid tribute to the club's academy staff for his development as a footballer.

"It has been brilliant," he said. "I came over when I was 15-years-old. Since then they have been looking after me brilliantly, so I have got to say thanks for that as well.

"My game has come on loads since I first came over. I was 15 and I was still learning. Obviously Tony McAndrew and Kevin MacDonald have been a big help in my career. They have been great to me."

* In other news, Herd's Australian teammate at Villa, Shane Lowry, has joined Championship club Sheffield United on loan for the remainder of the season. Click here to read the full story

Lowry joins another Australian youngster, Marc Warren, at Sheffield United, after he signed a two-year deal with the Blades from Central Coast Mariners. Click here to read the full story