Ricardo Carvalho and Eidur Gudjohnsen became Chelsea team-mates in 2004

Former Chelsea team-mates Ricardo Carvalho and Eidur Gudjohnsen are the two oldest outfield players to make it to Euro 2016.

What's more, the duo could even be up against each other in the Group F encounter between Portugal and Iceland in St Etienne on Tuesday evening.

That's despite one of them having made his international debut before Euro '96 and both men having seemingly retired from international football years ago. Here's their story…

Beginnings…

Gudjohnsen made his senior debut for Iceland as a 17-year-old against Estonia in Tallinn in April 1996. He came on as a half-time substitute for his own father, Arnor. While injury prevented the two ever getting onto the pitch for their country at the same time, the match does mean the international careers of the two men stretch back continuously to 1979.

The pair in action against Michael Ballack in the Champions League in 2005

In contrast, Carvalho was a relative late bloomer, not making his Portugal debut until 2003, at the age of 25. At that stage he was a Porto player under Jose Mourinho, having made his debut for the club as a 20-year-old, but there were also loan spells at Leca, Vitoria de Setubal and Alverca - all in the Portuguese top flight at the time.

Early success…

A broken leg playing for Iceland's Under-18 side curtailed Gudjohnsen's progress as a teenager at PSV but he bounced back to build a reputation for himself in England with Bolton. The top scorer for the Trotters in the 1999/2000 season with 21 goals, his form secured a £4m transfer to Chelsea in the summer of 2000.

Gudjohnsen in action for Bolton against Ipswich in a 1999 play-off game

Carvalho was almost a European Championship winner even before arriving at Chelsea but was denied on home soil by Greece in the 2004 final at the Estadio da Luz. It would have capped off the perfect summer as he'd already won the Champions League with Porto just prior to the tournament - following on from their UEFA Cup success the previous season.

Chelsea…

Gudjohnsen won a trophy - the Charity Shield - in his first game for Chelsea in 2000 but he then had to wait almost five years before his next piece of silverware with the club. The Blues did reach the last four of the Champions League in 2004 but were denied by Gudjohnsen's future club Monaco. All changed with the arrival of Mourinho that summer.

Carvalho has a strong bond with Jose Mourinho forged at three different clubs

The Portuguese coach signed Carvalho in a £20m deal and the defensive improvement reaped dividends as Chelsea won back-to-back Premier League titles - conceding only 15 goals in the first of those campaigns, still a record for an English top-flight season. At the other end, Gudjohnsen netted 12 times in the Premier League, outscoring Didier Drogba.

Since Chelsea…

After the second successive title win, Gudjohnsen joined European champions Barcelona in the summer of 2006. He became Iceland's all-time record goalscorer later that year before winning the treble with Barca in 2009. Further spells in England at Tottenham, Stoke and Fulham followed before an emotional return to Bolton in 2014 - a full 14 years after leaving.

The 37-year-old Gudjohnsen is Iceland's all-time record goalscorer

While Gudjohnsen's travels have also taken him to France, Greece, Belgium, China and Norway, Carvalho remained at Chelsea until 2010, collecting a third title with the club, before linking up with Mourinho again at Real Madrid. He featured in their title-winning season in 2011/12 before moving to Monaco in 2013.

Retirement…

Both Gudjohnsen and Carvalho had previously retired from international football well before Euro 2016. The latter's exit came amid acrimony when Paulo Bento accused him of deserting the team in 2011. Three years in exile were brought to an end by Bento's successor Fernando Santos. "I spoke with the coach and I told him that I felt I could help, so I said yes that he can call me because I am ready," said Carvalho.

Carvalho is now back in the Portugal squad under Fernando Santos

Gudjohnsen continued to play for Iceland during their encouraging World Cup qualifying campaign but play-off defeat to Croatia in 2013 looked to have brought his international career to a close - he was in tears after the match. "I'm pretty sure that was my final game for Iceland," said Gudjohnsen. And so it seemed until he made a goalscoring return in a Euro 2016 qualifier against Kazakhstan last year. For these two men, the story goes on…