Manchester United fans think Nottingham Forest's Aitor Karanka is Old Trafford-bound

Aitor Karanka, Manager of Middlesbrough smiles during the EFL Cup second round match between Fulham and Middlesbrough at Craven Cottage on August 24, 2016 in London, England.

Manchester United fans think Aitor Karanka could be heading to reunite with Jose Mourinho.

Aitor Karanka, Manager of Middlesbrough smiles during the EFL Cup second round match between Fulham and Middlesbrough at Craven Cottage on August 24, 2016 in London, England.

Manchester United ended their Premier League campaign with a 1-0 home win over Watford, and are now focusing on Saturday's FA Cup final against Chelsea.

The Red Devils finished second in the Premier League and can finish off with a piece of silverware, before embarking on what promises to be another big summer.

In order to catch Manchester City, United will need more big-money signings, and manager Jose Mourinho also needs to find himself a new assistant boss.

Rui Faria – who worked with Mourinho at Porto, Chelsea, Inter Milan, Real Madrid and United – has announced that he is leaving his role to become a manager himself elsewhere.

Real Madrid's Portuguese coach Jose Mourinho (R) chats with Real Madrid's assistant coach Aitor Karanka (L) during the second leg of the Spanish Cup quarter-final 'El clasico' football...

Whilst it's unclear who will replace Faria, Mourinho has given an interview to Record in his native Portugal about the situation, suggesting that he wants somebody he has worked with before, but can't reveal his identity as he is currently with another club.

That has set the United rumour mill into overdrive, and fans have taken to Twitter to guess that Nottingham Forest boss Aitor Karanka is the man Mourinho is talking about.

The Spaniard was Mourinho's right-hand man at Real Madrid before becoming Middlesbrough boss, and whilst Forest fans would no doubt be left stunned by Karanka leaving to become a No. 2, United fans truly think a move is on the cards.

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