12 12 12 6. Nathan Ake (Chelsea) – Underused since his return to Stamford Bridge from a loan spell with Bournemouth, the Dutch defender is versatile and likely to be used a lot more next year as Gary Cahill fades. His FA Cup semi-final display against Tottenham was arguably better than David Luizs as he helped keep them at bay. 3 Kurt Zouma (Chelsea) – Had it not been for a cruel long-term injury last season, and Chelseas title bid this campaign, the French youngster would have had a lot more games. Whether with the Blues, or someone else, were likely to see Zouma a lot next season. He is still a little raw, though. 12 10. Rob Holding (Arsenal) – Finally making an impact this season as the Gunners switch to a back three, ex-Bolton man Holding is showing promise. With so few opportunities to prove his worth, we cant hold him in higher esteem but if he continues in his current form hell move up this list reasonably quickly. 12 9. Ben Gibson (Middlesbrough) – Boro may have been relegated but Gibsons promise was shown as their defence, at least, gave them a fighting chance of staying up. Being left-footed makes him desired, while hes also quality with the ball at his feet. He does, perhaps, need to improve aerially. 12 8. Calum Chambers (Arsenal) – The centre-back has performed admirably at Middlesbrough and done exceedingly well in an inexperienced partnership with Ben Gibson. The loan spell has done him the world of good and Chambers should consider a move away from the Emirates again if he is to continue his development. 5. Michael Keane (Burnley) – The former Manchester United defender has been an important part of the Clarets miserly backline this campaign. Superb in the air, hes a maturing stopper with a good reading of the game. He also showed his adaptability by playing in a back three for England on his debut. 7. Harry Maguire (Hull City) – Finally showing his ability after being highly rated in his youth at Sheffield United, Maguire already has a host of clubs interested in his services, including Tottenham. Hes been a rock at the back for the Tigers and is impressing with his use of the ball as well as his defensive capabilities. 12 11. Mason Holgate (Everton) – At the moment, Seamus Colemans injury means Holgate is getting time at right-back, but previously he has also shown his ability at centre-back in a back four or a back three. He appears to time tackles well, and reads the game well as a whole. 12 12. Alfie Mawson (Swansea City) – Considering the 23-year-old stepped straight up from Championship side Barnsley to a Premier League relegation battle, Mawson has acquitted himself well. Hes still a little raw but has the tools to have a successful Premier League career. Middlesbrough may have been relegated back to the Championship but some of their players have impressed.Centre-backs Ben Gibson and Calum Chambers, who was on loan from Arsenal, performed admirably in their miserly defence.If they had been better in attack, there is no doubt the duos performances would have received far more attention, especially as they are both young and English.But who are the best centre-back under-25 in the Premier League? Click the right arrow above to find out how we have rated the top 12… 4. Eric Dier (Tottenham) – Spurs and England star Dier has continued his progression this campaign but debate will rage over whether his best role is as a defensive midfielder or centre-back. There is no doubt he is proficient in both roles and while he is possibly better in midfield is assured on the right side of a back three, rather than a back four. 12 12 12 2. John Stones (Manchester City) – Whisper it quietly but, despite the narrative suggesting Stones may be overrated and still in need of a mature sidekick, the England man is becoming a star at the Etihad Stadium. His ability in possession has come on even further, and he is stepping up in big games too. 12 1. Eric Bailly (Manchester United) – A summer signing from Villarreal, Bailly is still only 23 but has impressed with a series of mature performances at the heart of the Red Devils defence either side of an injury. Comfortable in possession and ready to battle with opposing strikers, he has the potential to be a big player at Old Trafford for years to come.