Boss Chris Hughton is concerned about a World Cup hangover for his Albion stars as Leon Balogun comes to terms with another cruel injury blow.

The Seagulls' recent defensive signing is rated 50-50 for Nigeria's opening group game in Russia against Croatia tonight.

Albion also have Australian goalkeeper Mathew Ryan and Colombian left-winger Jose Izquierdo (below) at the World Cup.

The Argus: Ryan is in action against France today (11am), while Izquierdo's first match with Colombia is against Japan on Tuesday (1pm).

The Albion players report back to begin preparations for their second season in the Premier League on June 28 - the same day as Colombia's closing group fixture against Senegal.

Hughton is mindful of the impact the World Cup could have on Balogun, Ryan and Izquierdo.

He told The Argus: "It's always a concern, because you want them first day of pre-season with everybody else.

"There's no doubt there can be a little bit of a hangover after World Cup duty, depending on how far they go.

"For our three there will be bigger excitement. For some they were naturally going to be there.

"For our three it's such a massive occasion because, with all due respect to all of them, they are playing for countries who weren't guaranteed to be there.

"For a player at Man United with Spain or who ever, although it's a big deal they will have Champions League and European Championships.

"It's a massive deal for all three of them and it's just making sure they are able to come down from that."

The more immediate concern is the extent and nature of Balogun's injury, sustained during training on Wednesday. He missed training in Essentuki on Thursday and was sent for a scan.

He is a doubt against Croatia, World Cup semi-finalists 20 years ago, in Kaliningrad this evening (8pm).

It is the second successive injury blow in World Cups for the versatile Balogun, signed by Albion last month on a free transfer from Bundesliga side Mainz.

The 29-year-old was sidelined from the finals in Brazil in 2014 after a freak accident during his debut for Nigeria against Mexico in the build-up to the finals.

He fell over a pitch perimeter advertising board and fractured a foot.

The Argus: Balogun (above) told The Argus before heading for Russia it made appearing in the finals this time "even more special emotionally. A lot of people said then maybe his career is over. My club, Fortuna Dusseldorf, wouldn't give me a new contract, but I'm a very optimistic person. I got back up and here I am again."

It remains to be seen whether Balogun will be available to try to help Nigeria qualify from a group which also includes Lionel Messi's Argentina and Iceland, their second opponents next Friday.

Balogun's possible absence is a major setback for the Super Eagles. He has developed a good understanding with William Troost-Ekong during the reign of German coach Gernot Rohr.

Kenneth Omeruo is expected to deputise for Balogun against Croatia if he is ruled out as Rohr contemplates whether to start with a back three or back four.