Croatia, of course, were runners-up last time out in Russia after losing 4-2 to France in the final, while they also claimed a third-placed finish at their first ever World Cup in 1998.
Japan have certainly looked the more impressive of the two sides in Qatar, having beaten the 2010 and 2014 champions Spain and Germany respectively to top Group E.
However, Croatia have remained unbeaten in their three matches after two goalless draws against Morocco and Belgium sandwiched a comfortable 4-1 victory against Canada.
With most last-16 ties at this year's tournament looking fairly one-sided on paper, Monday's meeting in Al-Wakrah looks a fascinating battle, and one which could be set to go all of the way to penalties.
Since the round of 16 stage was introduced at the 1982 World Cup in Spain, there have been at least two matches in all 10 World Cups to have finished as a draw at full-time.
Japan's meeting with Croatia is the only match at this year's round of 16 where one team is not going in to the match as an odds-on favourite with most bookmakers, making it by far the most likely game to end as a draw, which would provide neutrals with the joy of extra-time and potentially penalties to watch unfold.
As mentioned, Croatia drew two of their three matches in Group F, while all of Japan's games were only separated by a single goal, showing how tight they were in their nature.
Moreover, each of these side's victories at the group stage came from behind, meaning neither nation would be likely to lose their cool should they concede first. This clearly boosts the chances of either team mounting a comeback, with the game unlikely to ever feel dead.
As such, we suspect that there is a strong chance of there being nothing to split these teams after 90 minutes on Monday, with both goalkeepers set to be called into action in the form of a penalty shoot-out should that continue to be the case after extra-time.
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How Japan could line up against Croatia
How Croatia could line up against Japan