Igor has been ruled out for the rest of the season.
But his fellow defender Lewis Dunk returns to the Albion squad they visit Ipswich Town.
Igor underwent surgery on a hamstring injury after limping out of the recent 1-1 draw with Arsenal.
He told fans via social media that the procedure had been successful but he faced several months on the sidelines.
Dunk was kept out of the FA Cup win at Norwich but has the green light for the trip to Portman Road and will train today Joao Pedro could also return. He will be checked after training today having twisted his ankle in training last week.
Head coach Fabian Hurzeler said: “We have to see today. He will train with the team and then we will decide.
“We won’t take any risks. Only if it’s a calculated risk and he feels well.
“That is the most important, that the player feels confident with his body.
“We won’t do any stupid things. We have to wait for training session today and maybe also tomorrow.
“It seems to be that he didn’t get into his rhythm but I talked to him yesterday for a long time and he is in quite a comfortable place.
“He enjoys it here, he is happy with the performances. Of course, he would like to be on the pitch every game but sometimes your body doesn’t want the same thing so you have to adapt.
“But I think he is in a good place. He is performing quite well when he is on the pitch.”
Hurzeler said Danny Welbeck is in contention to start at Ipswich and Diego Gomez is also likely to be involved.
Jack Hinshelwood, Mats Wieffer and Evan Ferguson are back in training.
Of the three, it appears only Hinshelwood has a chance of involvement on Thursday.
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