OLI SCARFF/Getty Images

Real Madrid could be ready to end their interest in Manchester United goalkeeper David De Gea, as Los Blancos prepare to capture Athletic Bilbao stopper Kepa Arrizabalaga.

Spanish journalist Pipi Estrada said the Bilbao starlet is set to move to the Santiago Bernabeu, negating the need for De Gea's services (h/t Jack Staplehurst of the Daily Star).

Speaking on TV programme El Chiringuito, Estrada said:

"Kepa and Real Madrid have already reached an agreement.

"There is only one detail—if he arrives in the winter or summer. Real Madrid wants Kepa to come in the winter market and would pay Athletic €5 million more.

"And there the problem would be that Kiko Casilla would have to find a way out.

"If Athletic accepts that amount that Real Madrid offers, it would be done in January."

PIERRE-PHILIPPE MARCOU/Getty Images

Kepa is De Gea's understudy for Spain, and the 23-year-old is one of the brightest talents in Spanish football.

He has started 10 games in La Liga this season and will challenge De Gea for a starting berth in the national side.

De Gea has developed into one of United's most important players since arriving at the club in 2011, and he would be impossible to replace in the short term.

The 'keeper has long been linked with a switch back to the Spanish capital after previously plying his trade at Atletico Madrid, but Kepa's potential arrival could see Los Blancos turn their interest to strengthening other positions in their squad.

Shaun Botterill/Getty Images

In other United news, Marouane Fellaini has reportedly turned down a new deal at Old Trafford, with Arsenal interested in taking the player on a free transfer next summer.

According to Richard Tanner of the Daily Express, the Gunners want to exploit the Belgian's contract situation because United coach Jose Mourinho does not want to sell the player in January. Fellaini is content at the Theatre of Dreams but wants improved terms in order to commit his future to the Red Devils.

Fellaini has become one of Mourinho's most trusted foot soldiers, and the big midfielder allows the Special One to diversify his tactics.

Bleacher Report's Dean Jones said he thinks Mourinho will want a big-money signing to replace Fellaini if the Belgium international were to depart—a move that could shape the Portuguese's future:

The player was hugely unpopular among fans under former coaches David Moyes and Louis van Gaal, but he has won over large swathes of the United faithful since Mourinho took charge in 2016.

Fellaini would be a hugely interesting free agent on the open market and can feature as both a defensive and attacking force.

Arsenal could house a player who offers more in the air while giving Fellaini a new platform and challenge at a major club.

Mourinho will likely be keen to retain the midfielder for his unique skill set, and it would be no surprise if Fellaini gets the deal he wants from his current employers.