Assombalonga arrived at the club in the summer with plenty of pressure on his shoulders following a £5m move from Peterborough United, and Stuart Pearce's assistant admits that he has been impressed by the 21-year-old after his latest eye-catching display.
"If you are going to be successful in this division then you need someone who is capable of scoring 25 goals, and we believe he falls into that category," Wigley told reporters.
"It is not just his goals, his work-rate, his attitude and will to succeed is great and he shows that every day. He makes life difficult for defenders. We haven't just brought a very good player to the club, we have brought an excellent professional to the club."
Assombalonga has scored eight goals in seven Championship matches this season.