Diego Costa will be 'best in the world', says new Chelsea star

Diego Costa attempting an overhead volley

The striker looks set to become the best number nine in the world, according to former Atletico Madrid and current Blues teammate Filipe Luis.

Brazilian international Luis was a key part of Atletico Madrid's La Liga winning side last season, and also of the side that reached the 2014 Champions League Final, and he and his teammate Diego Costa both made the switch to Stamford Bridge in the summer.

Whilst Costa made his debut in the opening game of the season, scoring the equalising goal - and Chelsea's first of the season - against Burnley, the 29-year old left-back could only watch on from the sidelines. Whilst disappointed that he failed to make his first-team debut, Luis would undoubtedly have been delighted seeing his former and current teammate impress as he did on his first ever Premier League start.

However, it is unlikely that Luis was surprised by the outstanding display, considering that he rates Costa as one of the best strikers in the world - and maybe already the best.

Speaking to the official Chelsea magazine, Luis praised his kinsman, and gave the Chelsea fans a hint at how the two Brazilians work together on the pitch.

The four-times capped international said: "Diego is an unbelievable player - you are going to love him, because he gives everything for the shirt.

"If he isn't already the best number nine in the world, he will be very soon. He's a brilliant player with a big heart and I'm very happy he's here with me because he'll help me grow as a Chelsea player.

"I know him very well and I know he fights for every ball. If I have won the ball in a forward area of the pitch, I know I have to look to give it to him because he is better than me in front of goal. So, I always try to find him, look where he is and get the ball to him, because I know he is going to score."

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The link-up play between the two La Liga winners could not be seen on Monday evening, although it was another full-back who created Costa's first goal in English football - with right-back Branislav Ivanovic's ball into the box causing confusion, allowing Costa to capitalise to strike the ball home.

Whilst Luis missed out on the opening weekend, he will be hoping to feature frequently in the Blues Premier League campaign, and if he can have the kind of impact upon Diego Costa as he did last year, the Brazilian-born Spanish international will be certain to increase upon his tally from Monday night.

Will Diego Costa become the best striker in the world?

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