Manchester City appear to be closing in on the signing of Erling Haaland.

According to the Daily Mail, Haaland has agreed a deal worth in excess of £500,000-per-week with the Citizens.

City are now expected to trigger his release clause of £63m and a deal should be completed in the next week or so.

That'll be a huge coup for City. He is already one of the best players in the world at the age of just 21 years old.

Had he not had a release clause inserted into his contract, they would undoubtedly have had to pay a much greater fee for his services.

Per Transfermarkt, the Norwegian star is rated the second most valuable player in the world and the most valuable player of his age group.

But who else is the most valuable player in the world for their age? Using Transfermarkt, we've named the most valuable player in the world for every age from 16-40.

STUTTGART, GERMANY - APRIL 08: Erling Haaland of Dortmund gestures during the Bundesliga match between VfB Stuttgart and Borussia Dortmund at Mercedes-Benz Arena on April 08, 2022 in Stuttgart, Germany. (Photo by Matthias Hangst/Getty Images)

STUTTGART, GERMANY - APRIL 08: Erling Haaland of Dortmund gestures during the Bundesliga match between VfB Stuttgart and Borussia Dortmund at Mercedes-Benz Arena on April 08, 2022 in Stuttgart, Germany. (Photo by Matthias Hangst/Getty Images)

(Player's age and market value correct as of April 19, 2022)

16: Roger Fernandes (Braga) - £3.6m

17: Gavi (Barcelona) - £54m

18: Jude Bellingham (Borussia Dortmund) - £67.5m

19: Pedri (Barcelona) - £72m

20. Bukayo Saka (Arsenal) - £58.5m

21. Erling Haaland (Borussia Dortmund) - £135m

22. Dusan Vlahovic (Juventus) - £76.5m

23. Kylian Mbappe (Paris Saint-Germain) - £144m

MADRID, SPAIN - MARCH 09: Kylian Mbappe of Paris Saint-Germain heads the ball during the UEFA Champions League Round Of Sixteen Leg Two match between Real Madrid and Paris Saint-Germain at Estadio Santiago Bernabeu on March 09, 2022 in Madrid, Spain. (Photo by Gonzalo Arroyo Moreno/Getty Images)

MADRID, SPAIN - MARCH 09: Kylian Mbappe of Paris Saint-Germain heads the ball during the UEFA Champions League Round Of Sixteen Leg Two match between Real Madrid and Paris Saint-Germain at Estadio Santiago Bernabeu on March 09, 2022 in Madrid, Spain. (Photo by Gonzalo Arroyo Moreno/Getty Images)

24. Ruben Dias (Manchester City) - £67.5m

25. Rodri (Manchester City) - £63m

26. Jack Grealish (Manchester City) - £72m

27. Bruno Fernandes (Manchester United) - £81m

28. Harry Kane (Tottenham Hotspur) - £90m

29. Mohamed Salah (Liverpool) - £90m

LIVERPOOL, ENGLAND - APRIL 13: Mohamed Salah of Liverpool runs with the ball during the UEFA Champions League Quarter Final Leg Two match between Liverpool FC and SL Benfica at Anfield on April 13, 2022 in Liverpool, England (Photo by Clive Brunskill/Getty Images)

LIVERPOOL, ENGLAND - APRIL 13: Mohamed Salah of Liverpool runs with the ball during the UEFA Champions League Quarter Final Leg Two match between Liverpool FC and SL Benfica at Anfield on April 13, 2022 in Liverpool, England (Photo by Clive Brunskill/Getty Images)

30. Kevin De Bruyne (Manchester City) - £81m

31. N'Golo Kante (Chelsea) - £45m

32. Ciro Immobile (Napoli) - £27m

33. Robert Lewandowski (Bayern Munich) - £45m

34. Lionel Messi (Paris Saint-Germain) - £54m

35. Luis Suarez (Atletico Madrid) - £9m

36. Manuel Neuer (Bayern Munich) - £12.6m

37. Cristiano Ronaldo (Manchester United) - £31.5m

MANCHESTER, ENGLAND - APRIL 16: Cristiano Ronaldo of Manchester United in actio during the Premier League match between Manchester United and Norwich City at Old Trafford on April 16, 2022 in Manchester, England. (Photo by Jan Kruger/Getty Images)

MANCHESTER, ENGLAND - APRIL 16: Cristiano Ronaldo of Manchester United in actio during the Premier League match between Manchester United and Norwich City at Old Trafford on April 16, 2022 in Manchester, England. (Photo by Jan Kruger/Getty Images)

38. Dani Alves (Barcelona) - £900k

39. Pepe (Porto) - £900k

40. Zlatan Ibrahimovic (AC Milan) - £3.6m

Transfermarkt have valued Haaland at £135m. Because of his release clause, City are potentially about to sign him for a fraction of his value.

Messi and Ronaldo, despite being 34 and 37 respectively, are still valued at £54m and £31.5m.

Mbappe is rated at £144m, making him the world's most valuable footballer.

He could well be on the move this summer on a free transfer, with his contract at PSG running out in a few months.

Real Madrid have been heavily linked and could get him for nothing.

Among the high-profile players that aren't the most valuable in the world at their age include Vinicius Junior (21), Neymar (30), Raheem Sterling (27), Sadio Mane (30), Son Heung-min (29), Luka Modric (36) and Karim Benzema (34).

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