Having failed to win promotion back to the Premier League at the first time of asking, Middlesbrough will have a real battle to keep hold of several key players.

Tony Pulis has several players in his squad who are attracting top-flight interest, with Adama Traore one man who may leave the Riverside given his talent.

Another is local lad Ben Gibson, who decided to stay with the Teesside outfit this season despite Premier League clubs chasing him last summer.

However, he may be more open to a move now and Everton and Southampton are both reportedly interested in the 25-year old.

With Boro knowing their parachute payments drop next year, they may already look to cut costs so failure to win promotion again doesn't have a major impact.

Here we look at three potential replacements should they cash in on Gibson...

The experienced defender will be released by West Ham in the coming weeks but could still do a job in the Championship and is the sort of no-nonsense defender that Pulis likes.

He has been linked with a move to the Riverside and could be the sort of dominant, leader figure to lead a promotion push.

Wolves will look to sell many fringe players after they won promotion and Batth would excel under Pulis.

Whilst limited on the ball, he is a strong, uncompromising defender and has proven himself to be a good operator in the Championship.

Flint would be the most expensive option out the three but he would still be available for a lot less than Boro will want for Gibson.

The Bristol City man is one of the best centre-backs outside the Premier League and is excellent in the air.

Again, he is exactly what Pulis looks for in a defender and would be a great replacement.