Grady Diangana will remain at West Brom this season

Snapped up on a temporary basis from West Ham in August, Diangana has been integral to the Baggies' rise to the top of the Championship.

The Hammers had the option to recall the winger – who is currently sidelined with a hamstring/back injury – from his loan at The Hawthorns this month.

The Premier League outfit, who the Baggies face in the FA Cup tomorrow, initially had until January 27 to make a decision – but it is understood Albion have paid a small fee to remove that recall option.

Diangana first picked up an injury to his back and hamstring during the 3-2 win at Blues last month.

He then suffered a recurrence of the problem during Monday's defeat to Stoke. But despite the knock, Bilic admitted he is thrilled to be keeping the player at The Hawthorns.

“He is staying with us – we are delighted with that," the head coach said.

"The club has done a good job, a brilliant job.

"That’s what we’ve been trying to do and we’ve put a lot of effort in over the last six weeks to try and keep him with us at least until the end of the season.

“That’s what he wanted, big time.

"Okay he got injured, as you know, against Stoke, but I’m so happy that he’s staying.

“He should be back for a crucial stage of the season. We are not talking about days, we are not talking about months - we are talking about weeks.

“You never know, but he’ll be back when we really need him. We need him now - but the key information is that he’s staying with us.”

As well as Diangana staying at The Hawthorns, the Baggies have received more good news with youngster Dara O'Shea committing his long-term future to the club.

The promising defender will sign a three-and-a-half-year deal once training is completed today.

“Dara has signed a new contract which is brilliant for us, I’m delighted with that," Bilic added.

“He’s top and I love Dara. He is the reason why we are not getting the players in those positions.”