For professional footballers there are few landmarks more important than claiming your first international cap. 

Despite the disdain which many fans show towards international football, the opportunity to play for the national side remains a distinct source of innate pride for players. 

The first cap often represents the culmination of promise, form and hype at club level, with the step up offering players an opportunity to showcase their quality under the spotlight of a larger, national audience. 

Many players across the globe were handed their first international appearance during a year in which the very essence of international football was scrutinised amid the added physical demands imposed on players in light of the coronavirus pandemic. 

With that in mind, GIVEMESPORT have rounded up the 20 most valuable international debutants of 2020 courtesy of data provided by Transfermarkt.

The list includes a hefty total of six England players and just one non-European player. 

Take a look at the most highly valued debutants of the year below...

20. Unai Simon (Spain - €30m)

Athletic Bilbao's in-house replacement for Kepa Arrizabalaga was handed his first Spain cap in a 1-1 draw against The Netherlands in November. 

The 23-year-old's impressive rise suggests he can establish himself as his nation's number one. 

19. Manuel Locatelli (Italy - €30m)

Roberto Mancini brought Sassuolo's Manuel Locatelli into the Italy setup back in July. 

The Azzurri have won all four of the games Locatelli has started since he made his debut. 

18. Trincao (Portugal - €30m)

Trincao's debut for the Portugal national side pre-dated his transfer to Barcelona in August.

Could the 20-year-old be his country's successor to the indomitable Ronaldo?

17. Giovani Reyna (USA - €30m)

One of Borussia Dortmund's collection of precocious youngsters made his USA debut as a 17-year-old in November in a 0-0 draw with Wales. 

And he scored his first goal for the national side just four days later with a well executed free kick against Panama. 

16. Mikel Merino (Spain - €35m)

The ever impressive Mikel Merino continues to realise the potential many Newcastle fans saw in him during his one-year stay on Tyneside. 

Merino made his debut in September and has added a further five caps since. 

15. Reece James (England - €35m)

Trent Alexander-Arnold's status as England's first choice right-back has been clouded by the emergence of Reece James. 

Gareth Southgate thrust him into the Three Lions setup in August and handed him a pair of starts against Denmark and the Republic of Ireland towards the end of the year. 

Along with Kyle Walker, Kieran Trippier and Aaron Wan-Bissaka, the race for England's right-back berth is on ahead of Euro 2021. 

14. Adama Traore (Spain - €40m)

Everyone's favourite speed machine was rewarded for his fine club form with a total of five Spain caps this year. 

The form he displayed for Wolves in 2019/20 has faded this season and he'll need to rediscover that in the new year to ensure he earns a place in Luis Enrique's squad for the Euros. 

13. Marcus Thuram (France - €40m)

You have to be a serious player to get into the France squad, just ask Aymeric Laporte. 

Despite the plethora of options available to Didier Deschamps, Borussia Monchengladbach attacker Marcus Thuram, who typically operates from the left wing, made his Les Bleus debut in November. 

No mean feat for a player who continues to star in the Bundesliga. 

12. Bukayo Saka (England - €40m)

Infectiously likeable, adaptable and tangibly mature beyond his years, Bukayo Saka has been one of the breakthrough stars of 2020. 

The 19-year-old has been a revelation at Arsenal and Southgate handed him a deserved four England caps as the year edged towards its conclusion. 

11. Marcos Llorente (Spain - €45m)

Most will remember Marcos Llorente as Liverpool's Champions League nemesis who effectively knocked the holders out of the competition with a stunning brace at Anfield in March. 

The 25-year-old's 18-minute cameo against The Netherlands in November was his first and only Spain appearance to date.

10. Dominic Calvert-Lewin (England - €45m)

Few predicted Dominic Calvert-Lewin's rise but he's now one of the most prolific forwards in the Premier League. 

With a refined sense of how to find the back of the net installed in him by Carlo Ancelotti, Calvert-Lewin caught Southgate's eye this year and pulled on the England shirt five times in total. 

9. Alessandro Bastoni (Italy - €45m) 

Alesandro Bastoni, 21, is shaping up to be the next elite central defender to emerge from Italy. 

A regular for Serie A title-chasing Inter Milan, Bastoni has kept clean sheets in all three of his outings for his national side. 

8. Jack Grealish (England - €50m)

Jack Grealish is something of a throwback to the England players of yesteryear who dominated tabloid pages with their off-field antics, but driving offences and divisive haircuts don't appear to be halting his progress on the field. 

Following months of outcry from the British public, Southgate finally gave Grealish his long overdue reward in August for his consistently insatiable displays for Aston Villa.

Grealish, who is the Premier League's highest performing player this season according to Whoscored data, will be gunning to convince his national manager that he should be in the starting XI when the Three Lions begin their Euro campaign against Croatia in June. 

7. Houssem Aouar (France - €50m)

Houssem Aouar was mooted as a target for Arsenal for the majority of the summer window but remains contracted to Lyon. 

His displays in central midfield caught the eye domestically as well as on English shores, with Deschamps handing the 22-year-old his France debut against Ukraine back in July.

Aouar provided two assists in the 7-2 demolition.

6. Ferran Torres (Spain - €50m)

Manchester City newbie Ferran Torres has enjoyed a meteoric rise for both club and country this year. 

Having made his Spain debut against Germany in September, the 20-year-old now has four goals from seven international appearances and he's rapidly adapted to life in the Premier League since leaving Valencia. 

5. Mason Greenwood (England - €50m)

Mason Greenwood earned his first cap in September in what has been a challenging year for the 19-year-old. 

Man United's prodigy is yet to hit the heights expected of him, but it won't be too long before he's adding to his one England appearance if his flashes of clinical finishing are anything to go by. 

4. Eduardo Camavinga (France - €50m)

That Eduardo Camavinga was handed his international debut for the World Champions before his 18th birthday attests to the enormity of his potential. 

The central midfielder has since added two more caps to his collection and notched his first goal against Ukraine in October, which made him the second youngest goal scorer in France's history after the late Maurice Gastiger. 

3. Dayot Upamecano (France - €60m)

RB Leipzig's colossal centre back made his debut in a 1-0 win against Sweden in September. 

The 22-year-old has made a further two appearances in what promises to be the beginning of a long and fruitful career. 

2. Phil Foden (England - €60m)

The most naturally talented star from the England squad that won the U17 World Cup in 2017 made his senior debut against Iceland in September in light of his increased involvement for Manchester City. 

Debate over whether Pep Guardiola is handing him sufficient minutes will continue to dominate the discourse surrounding Phil Foden, but his standout display in England's 4-0 victory over Iceland in November, in which he scored two and assisted one, pointed towards an auspicious future. 

1. Ansu Fati (Spain - €80m) 

The most valuable player on the list is up there with the most exciting prospects in world football.

Not only did Ansu Fati make his debut against Germany in September, he also became the youngest scorer in Spain's history during a 4-0 win against Ukraine just three days later. 

His €80m Transfermarkt valuation gives an indication into what lies ahead for the 18-year-old sensation.