The Celtic midfield could undergo some restructuring this summer. Some key midfielders look to be on their way out and will need replacing.

Reo Hatate is believed to have asked to leave. And considering how little football he played towards the end of last season under Martin O'Neill, who will be returning as permanent manager, one would imagine his wish will be granted.

Arne Engels could be on his way out as well. Nottingham Forest, Sunderland and Fulham are all believed to be interested in the Belgian.

In fact, Nottingham Forest are said to have made a failed £25 million bid in the winter. While Celtic might have turned it down in the middle of the season, they might not have the same resolve in the summer. If a similar offer comes in, expect Engels to be gone.

Then there is Benjamin Nygren, the club's top scorer and player of the season from last season. He is being linked with a move to the Premier League as well and an exit has not been ruled out. The World Cup could end up having an impact on this as well.

So, Celtic will need to bring in some quality midfielders as replacements. And it looks like a former Liverpool player is on their radar.

According to Sebestien Vidal, Celtic were advancing on several fronts to strengthen their squad this summer. One of the players the Scottish champions are following is Bobby Clark.

That will be a familiar name to Celtic fans. That is because the Hoops have been linked with the midfielder, going back to his time at Liverpool.

There were rumours about a move last summer as well, but it did not end up happening once again. Could that change this time around?

Clark spent the season out on loan at Derby County and did well. So much so that it has caught the eye of several clubs.

Even West Ham United, who have just gone down to the Championship, are rumoured to hold an interest in the former Liverpool midfielder.

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Clark is currently on the books at RB Salzburg, who spent £10 million to sign him from Liverpool. One would imagine that they would want to at least recoup that.

Some fans might raise an eyebrow at the fact that Clark spent the season out on loan in the Championship rather than staying with the club that spent a significant figure to sign him. Is that a sign that even the Austrian top flight is proving too difficult for him? If so, is he someone cut out to get the job done for Celtic, where the pressure will be even higher?

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