Delph has featured in all three of the Villans' Premier League fixtures against Arsenal, Chelsea and Liverpool respectively.
"Fabian has been immense, incredible," Westwood told the club's official website. "Last year he was unbelievable. He's taken that on already this term.
"I enjoy playing with him very much. We combine well. I hope he keeps this form up throughout the season. I am sure he will."
Villa are back in action on Wednesday when they host Rotherham United in round two of the Capital One Cup.