Youngster David Edgar is ahead of Diatta in the pecking order, and KK wants to bring in another top quality central defender in time for the new Premiership campaign.
That seems to rule out both Diatta and Peter Ramage.
One player pleasantly surprised at getting a spell in the first team is David Edgar, who has revealed his delight that Keegan has kept faith in him despite some dodgy performances.
Edgar: "It's exciting that the gaffer shows some faith in me.
"I thought I did OK against Reading and West Ham after shaky starts so I'm glad the gaffer gives me that opportunity - especially with a player of Lamine Diatta's quality on the bench.
"Hopefully, I've done enough to stay in the team. If Abdoulaye is fit then I'm likely to be on the bench again but that's fine as I'm just excited to be involved again.
"At West Ham I learned a lot.
"I played against two different types of players in Bobby Zamora and Dean Ashton. Ashton is a strong player and an England international.
"But once I realised what they wanted to do, I played better and didn't let them dominate me.
"It was a good experience. At West Ham we were lucky to be level at half-time but we could have won the game.
"However, the plus point was that we haven't lost a game.
"We want to end on a high and it's important not to lose any more games.
"At the start of the season I was in and around the first team picture.
"But since KK returned he has given me my chance. I feel I have done well in front of him and it's great to be around him. You want to be involved with the first team, week-in week-out."