Can you remember what you were doing on 1 March 2006? Perhaps you were at Anfield, watching England beat Uruguay 2-1. You might have seen Switzerland put three goals past Scotland at Hampden Park.Or you might have watched Luka Modric make his debut for Croatia. They beat Argentina 3-2, with Lionel Messi scoring his first international goal. The same evening, Cristiano Ronaldo scored twice in a 3-0 Portugal victory against Saudi Arabia, no doubt dreaming of the day he would live and work in the country.While he and Messi have dominated football discourse since then, Modric has been there throughout too. In a more metronomic, less flashy, passing-more-often-than-scoring kind of way, granted, but as another constant presence at the top level.The trio are in an elite group of four men who have accumulated at least 200 international caps. Claim a bonus point if you can name the other.Chart showing the top 10 footballers for international capsRonaldo, 41, and Modric, 40, will make their 232nd and 202nd appearances respectively for their countries when Portugal face Croatia in the last 32 of the World Cup . It will probably could be the final time these giants of 21st-century football share a pitch after careers that have intertwined as opponents and teammates.Their shared commitment to international football is to be applauded. Ronaldo had won 29 caps when Modric made his debut for Croatia. It is more than 20 years further on, but the gap has only widened by one. The pair have always answered when the call has come from their countries, playing games at near-parallel rates.Chart showing the cumulative international appearances of Luka Modric and Cristiano RonaldoTheir paths first crossed in 2008‑09. Modric and Ronaldo played the whole game (and got a rating of 7) in the Carling Cup final that season, with Manchester United beating Tottenham on penalties. They later met in the quarter-finals of the 2010-11 Champions League after Ronaldo had moved to Spain.Real Madrid prevailed in that tie, as they so often did in the six seasons when the pair represented the club. They won the Champions League four times together, reaching the semi-finals in the other two campaigns.skip past newsletter promotionafter newsletter promotionIf they had a shared pinnacle moment, it was Modric cutting the ball back to Ronaldo for him to put Madrid 3-1 up against Juventus in the 2017 final. It was one of the 222 matches when they shared a pitch. It makes Modric the central midfielder with whom Ronaldo has played most times.Chart showing Cristiano Ronaldo’s 10 most frequent teammatesToronto will host the fifth international meeting of the duo, with Portugal having won the first four. Whether Modric’s Croatia finally claim a victory or not, the match will be remembered far more than some international friendlies from 2006.