West Brom boss Sam Allardyce admits Dara O'Shea has given him a selection headache following the defender's impressive performances in their last two games.
The centre-back then put in another excellent display to help the Baggies secure a 1-0 win over Brighton on Saturday.
Ajayi was suspended for that match but the Nigerian international is now available for the visit of Everton on Thursday.
"Absolutely – we got a clean sheet and Dara has performed very well," Allardyce said when asked if O'Shea has given him a selection headache ahead of Everton.
"Dara was unlucky to be left out the side anyway. He did a job for us filling in in a few different positions and then found himself left out the team which is very disappointing.
"He wouldn't have looked upon me as the kindest because it was me who shifted him about and then left him out.
"He must have thought if he had stayed where he was he would have kept his place in the side. But he is a good, honest, lad and tries to help the team out.
"But Semi and Barts (Kyle Bartley) were playing okay."