Mexico failed to qualify for the knockout stage of the 2022 FIFA World Cup via goal difference, though the story of their chaotic exit is far deeper than that.

El Tri beat Saudi Arabia in their final group stage game on Wednesday, winning 2-1. Meanwhile, Poland lost to Argentina 2-0 as Lionel Messi and co. topped the group to advance. Despite their contrasting results, though, it was Poland who qualified for the Round of 16.

The reason is quite simple on the surface level. Both teams accumulated four points after having one win, one draw and one loss each. With that, the tiebreaker ended up being the goal differential—which is basically the number of goals scored minus the number of goals allowed by a team.

Mexico scored a total of two goals in the competition, but they allowed three to be scored against them, leading to a goal difference of -1. Meanwhile, Poland scored two goals and only allowed two as well for a zero goal difference.

Nonetheless, it is worth noting that there's a reason why Mexico tried hard to score more goals against Saudi Arabia, which is obviously a strategy that backfired after Saudi scored one against them. Had Mexico won 2-0 as well and made their goal difference zero similar to Poland, they would still not qualify because of fair play rules.

In that scenario, Mexico and Poland would have been tied in points, goal differential and goals scored. The head-to-head results won't matter as well since Mexico and Poland played a 0-0 draw in their World Cup opener. With everything tied, Poland would move on via virtue of the “fair play” tiebreaker that considers the number of yellow and red cards. Mexico had two more yellow cards than Poland.

It is the first time since 1990 that Mexico failed to qualify for the knockout stage of the World Cup. And that year, they only didn't make it because they were banned from the tournament. The last time they didn't make it out of the group stage despite playing was in 1978.

Of course it is a big disappointment for Mexico, but at the end of the day, they have no one to blame but themselves for their shortcomings early on.