The Baggies boss does not want to even contemplate the possibility of the 25-year-old not returning.

"I will be extremely disappointed if it doesn't happen, I don't even want to think about it," said Bilic, whose side face Everton at Goodison Park in the Premier League on Saturday.

"Every day when I walk into the training ground I ask about him. Why? Because last year he played a lot of games for us.

"He was brilliant on the pitch. You can be versatile with him on the pitch, you can change systems without changing the players.

"He improved a lot. He started to shoot on goal, to score goals. He got assists. Everybody loves him. He makes every player around him better – he is one of those, a silent or unsung hero.

"That is why every day I ask has he come, is it improving, is it improving? That's how high I value him."

Asked why a deal to bring back Krovinovic has yet to materialised, Bilic said: "Budget. We have to find some money for a loan or whatever.

"He (Krovinovic) wants to come. Everybody wants him here. I heard there is a possibility also from Benfica – that is why I am optimistic regarding Filip.

"As I said, I would be very, very disappointed if he doesn't come back.

"All that I know is that the people inside the club – the people at the training ground on a daily basis – they are doing their best.

"How much resources they have is not a question for me. I am not the financial director."

Matt Phillips and Conor Townsend could be in Bilic's Premier League squad for the first time this season at Everton.

Both players missed the opening-day defeat to Leicester – Phillips with a back injury and Townsend due to an ankle problem – but they each featured against Harrogate in midweek in the Carabao Cup.

Young midfielder Conor Gallagher has joined on loan from Chelsea in time for the match on Saturday but fellow new recruit Branislav Ivanovic is still building up his fitness. Ahmed Hegazi (hamstring) and Kenneth Zohore (calf) remain doubts.