Having been banned from making any signings in the recent winter transfer window, Real Madrid are expected to splash the cash this summer.

While it's hard to pinpoint any major flaws in their current squad, Zinedine Zidane will know there is always room for improvement and look to bolster his side.

In truth, you could hardly blame the Frenchman if he ended up sticking with his current crop of players following what has been - and should end up being - a phenomenal season.

Not only do they still have the advantage over Barcelona in the La Liga title race with a game in hand, but they also have one foot in the Champions League final.

Cristiano Ronaldo's hat-trick against Atletico Madrid on Tuesday night gave Real a comfortable 3-0 lead heading into the semi-finals second leg next week.

So where can Real really improve? For a start, there are arguments to be made that they can do better than Keylor Navas and Karim Benzema.

While Navas isn't quite regarded as a world-class goalkeeper, Benzema has produced hit and miss performances this season.

A new winger might even be necessary considering Ronaldo is gradually evolving into a central striker and Gareth Bale's injury problems.

It's no surprise, then, that Real are reportedly interested in Manchester United's David de Gea and Chelsea star Eden Hazard.

However, in Roberto Carlos' opinion, there is one other Premier League player that Zidane should try to sign this summer: Tottenham's Dele Alli.

According to The Sun, the former Brazil left-back is a huge admirer of Alli who, at the age of 21, he believes is already good enough to play for Los Blancos.

Asked if he would sign the Englishman for Real, Carlos replied: "Yes, definitely! He's a brilliant player. I love him, I've seen him play some great games in England.

"Of course, it's not up to me - transfers will, of course, be decided by the president. But we definitely could sign him. He is undoubtedly good enough for Real Madrid."

Praise doesn't get much bigger than that. Despite Carlos' wishes, the chances of Alli joining Real this summer are slim after Mauricio Pochettino insisted he is going nowhere.

But should Zidane pursue Alli, Hazard and De Gea's signatures, he can't go far wrong.

All three have been brilliant in the Premier League this season and would take Real to the next level - if that's at all possible.