As we move into the summer, the best players in the world are becoming subject to transfer bids as the top sides in Europe attempt to strengthen their teams.Players are being given huge price tags as their current clubs look to hold onto their star men.Liverpool winger Raheem Sterling is just one footballer likely to move for a princely sum in the next few months.But while teams quibble over a fee, some boffins over in Switzerland have done some number crunching to figure out what a reasonable figure would be.So, thanks to the guys over at the *CIES Football Observatory, a reserach group affiliated to the University of Neuchatel in Switzerland, we can tell you the most valuable players in the world.Click the right arrow to find out which superstar is worth the most… 17 17 17 17 17 15. Harry Kane (Tottenham) is valued between €53.5m-€58.9m – Click right to find out the world’s most valuable players… – Its been a sensational season for the Spurs starlet. A relatively unknown player outside the club, Kane didnt start his first Premier League game of the campaign until November but ended it as the divisions second highest scorer with 21 goals. His incredible performances have seen his value rocket but he will need to prove he isnt a one-season wonder. 14. Isco (Real Madrid) is valued between €57.2m-€62.9m – Click right to find out the world’s most valuable players… – While Gareth Bales value is dropping, Iscos is rising in the Spanish capital. Hes much-loved by the clubs fans and while hes not really prolific when it comes to scoring, hes true skill comes with his dribbling and ability to retain possession. 3. Cristiano Ronaldo (Real Madrid) is valued between €113.3m-€124.7m – Click right to find out the world’s most valuable players… – A shock at No.3, the Portuguese superstar may have had another stellar season in the Spanish capital but his age, and a trophyless campaign, mean his value is slowly beginning to drop at the Bernabeu. 17 17 17 4. Neymar (Barcelona) is valued between €89.6m-€98.5m – Click right to find out the world’s most valuable players… – After a tough start to life in Spain, with his transfer from Santos under investigation and his performances and slight frame facing scrutiny, Neymar has gone on to prove himself as one of the best players on the planet. Winning the treble this season after his talismanic performances for Brazil at last years World Cup will be a huge relief for the 23-year-old. 10. James Rodríguez (Real Madrid) is valued between €62.5m-€68.8m – Click right to find out the world’s most valuable players… – The Colombian playmaker has had a decent first season in La Liga, despite Real Madrid finishing without a single trophy to their name. Second only to Cristiano Ronaldo when it comes down to the most goals and assists for the club, hes settled well and will hope to kick on next year. 17 17 8. Diego Costa (Chelsea) is valued between €69.9m-€76.9m – Click right to find out the world’s most valuable players… – An instant hit in the Premier League for Chelsea, Costa has replaced Luis Suarez as the English top flights pantomime villain. Hated for his histrionics, his rough-housing of opponents but praised for his old-school centre forward play, the Spain international was a key member of the Blues title winners. 17 9. Alexis Sánchez (Arsenal) is valued between €67.8m-€74.6m – Click right to find out the world’s most valuable players… – Arsene Wenger struck gold when Barcelona decided to ditch Sanchez and sign Luis Suarez. The industrious Chilean has been a superb addition to the ranks at the Emirates thanks to his goals and his work rate. A thunderous effort in the Gunners FA Cup final win over Aston Villa summed up his season. 7. Paul Pogba (Juventus) is valued between €70.3m-€77.3m – Click right to find out the world’s most valuable players… – Probably the hottest prospect in European football, Pogba is wanted by Barcelona and Manchester City, amongst others, after some monstrous performances for the Italian giants over the last two campaigns. Expect this to be the longest running transfer saga of the summer if clubs can afford this huge fee. 17 17 12. Antoine Griezmann (Atlético Madrid) is valued between €59.0m-€64.9m – Click right to find out the world’s most valuable players… – One of the biggest hits in La Liga last season was France star Griezmann. Brought in from Real Sociedad for £24m after impressing at the World Cup, hes gone on to prove himself one of the brightest talents in Europe. Under Diego Simeone he scored 22 league goals as they fell short of retaining their title in Spain. 6. Raheem Sterling (Liverpool) is valued between €73.7m-€81.0m – Click right to find out the world’s most valuable players… – It seems almost certain the England winger will be leaving Anfield this summer, despite his destination being unknown. The Reds will need to be suitably compensated for the 20-year-old sensation and if the CIES Football Observatorys figures are anything to go by they can expect a huge sum. 17 11. Luis Suárez (Barcelona) is valued between €60.0m-€66.0m – Click right to find out the world’s most valuable players… – After being the star turn in Liverpools SAS, hes now a worthy member of MSN over in Catalonia and a Champions League final goalscorer for five-time champions Barcelona. Strangely, the striker who was sold by the Reds for £75m has lost some value but, after winning the treble, his current club wont care a jot. 5. Sergio Agüero (Manchester City) is valued between €78.2m-€86.0m – Click right to find out the world’s most valuable players… – As the Premier Leagues top scorer, its understandable the Argentine forward is valued so highly by CIES. His clinical performances across the last four seasons, despite injuries restricting his appearances, see him rated as one the top five most valuable stars in world football. 17 17. Philippe Coutinho (Liverpool) is valued between €50.4m-€55.5m by the CIES Football Observatory* – Click right to find out the world’s most valuable players… – Rated as one of the top six players in the Premier League by his peers, and arguably Brendan Rodgers best signing at Anfield, Coutinho has come a long way in his two and a half years at Liverpool. Signed for £8.5m hes now rated well above that and would make the Reds a tasty profit. 17 16. Gareth Bale (Real Madrid) is valued between €51.3m-€56.4m – Click right to find out the world’s most valuable players… – After a tough second season in Spain, the Welsh winger has seen his value begin to diminish. Signed from Tottenham Hotspur for around £85m, the 25-year-old is reportedly worth just over 50m now, and while the wealth of Real means it wont bother them too much, it is indicative of his waning influence at the Bernabeu. 17 1. Lionel Messi (Barcelona) is valued between €255.3m-€280.8m – Its unsurprising to see Messi on top of this list. The Argentine wizard, after becoming a bit leaner, has gone from strength to strength following a slight dip in performance levels midway through the campaign. In total he hit 43 La Liga goals and set up his team-mates on 18 occasions, but despite being valued so highly its unlikely anyone will every be able to afford his services until later in his career. 13. Cesc Fàbregas (Chelsea) is valued between €58.7m-€64.5m – Click right to find out the world’s most valuable players… – Landing the Spanish star from Barcelona was a masterstroke from Jose Mourinho last summer. His sensational early season form put the Blues well out ahead of their Premier League title rivals and having lifted the trophy come the end of the campaign, Roman Abramovich will consider his transfer fee £30m well spent, especially as the CIES Football Observatory rate him at double that now. 2. Eden Hazard (Chelsea) is valued between €135.4m-€148.9m – Click right to find out the world’s most valuable players… – The second most valuable player in the world is, in fact, Belgian star Hazard. His peers rate him as the best footballer in England after helping Chelsea to the Premier League title and although he might not get the amount of goals and assists as someone like Cristiano Ronaldo, his input is more vital at Stamford Bridge.