#1 Raheem Sterling (Manchester City)
There is no doubt Raheem Sterling has been Premier League's best player this season.
Even if Virgil van Dijk won the PFA Player of the year for his amazing defending for Liverpool, Sterling has been an explosive offensive player in the Premiership this season. No defender would fancy playing against the young man.
Since Guardiola's arrival at City in 2016, Sterling has become a monster under the tutelage of the Spanish coach, who has coached Barcelona earlier and has won the best of all accolades with the Blaugranes. Not to miss, Guardiola has a special relationship with Messi, who many fans feel has the biggest role in the Argentine becoming the best of all time.
Sterling is only 24 right now, and looking at the growth of the player in the last 2 years, there is no doubt that he will be one of the best in his position in the next 2 years or so, definitely a top 3 contender for the best wingers in the world.
He also scores a lot of goals for his club, if not as much as Messi does, but he is not very far. Sterling has 22 goals and 10 assists for City this season in all competitions.
Though replacing Messi is going to be a herculean task, Barcelona should start preparing for the same, as the Argentine is going to leave a huge void at the club on his departure, or shall we say retirement, as it is very unlikely that Messi will leave Barcelona for another club.