Man City inserted an ANTI-Man United clause into Diaz's Real Madrid deal

Manchester City insisted on a clause that would deter Real Madrid ever selling Brahim Diaz to Manchester United when they let the youngster join the Spanish side.

Should Madrid decide to let Diaz go to Old Trafford in the future, they would have to pay City 40% of any transfer fee according to Marca.

Pep Guardiola was keen to keep the forward at the Etihad but Diaz wanted more first team minutes and with his contract coming to an end, City were forced to sell in January 2019 instead of losing the Spaniard for free.

But the inclusion of this clause to hamper any move to their Manchester rivals shows just how highly Diaz's former club rate him.

The 21-year-old joined Madrid for £15.5m, on a long-term contract running until 2025, but was still far from a regular in the team.

Diaz signed for AC Milan on loan at the start of this season, and has enjoyed the most sustained run of first team football in his career so far.

He has already made 17 Serie A appearances, including ten starts, and found the back of the net three times in the Europa League group stages.

And the Spaniard, who has played five times for his country's U21 side, made his return to England on Thursday night in the first leg of Milan's last 16 Europa League clash with Manchester United.

Diaz started against Ole Gunnar Solskjaer's men and played 69 minutes before being substituted in the 1-1 draw.

The Italian side are looking to reach the quarter finals of European competition for the first time since the 2011/12 campaign, when they were defeated in the last eight of the Champions League by Barcelona.

It remains to be seen whether Diaz's stay in Italy is extended next season, but the youngster has impressed regardless in a campaign that sees Milan second in Serie A, six points behind their big rivals Inter Milan.