The thrashing handed out by Spain on Tuesday evening in Madrid was the joint-worst defeat in the history of the Argentina national team, equaling the 6-1 scorelines suffered against Czechoslovakia in the 1958 World Cup and away to Bolivia in qualifying for the 2010 tournament. It laid bare (if that were needed after the qualifying campaign) some serious problems in Argentina's preparations for this year's World Cup.

Here are six reasons things that went so badly wrong for Argentina -- one for each goal they conceded.

1. Even pre-match, injuries were a problem

There was the injury to Lionel Messi, of course. Having the team's key player sit out both matches of this doubleheader of friendlies was far from ideal, and would have remained a black mark even if Argentina had strolled to victory without breaking a sweat in both matches. If Jorge Sampaoli wants the best look at the players he's considering for the squad, particularly in attack, then he wants to see how they play with Messi, because that's really the most important question any Argentina manager has to consider at present. But beyond Messi's issue, it was also a blow to lose Manuel Lanzini, who'd impressed against Italy, and to have to do without Sergio Aguero, who seems to be plainly the team's first-choice No. 9 now.

2. The opening goal caused two problems in one

Considering the Brazilian-born forward's reputation as both an excellent striker and a master of football's dark arts, the opening goal was perhaps the most Diego Costa thing ever to happen. Not only did it give his team the advantage, it also injured their opponent's goalkeeper. That might work out as a good thing for Sergio Romero personally. If Willy Caballero was a candidate to take the first-choice goalkeeping role from him after impressing against Italy, he'll surely find that a harder battle to win after letting in five goals from as many shots on target. In the context of an individual match, though, having to change goalkeepers so early on (even if Romero did last another 10 minutes before succumbing and asking to be subbed) is never useful for a defence.

3. Javier Mascherano

He's a national team legend for his performances at the 2014 World Cup, but in the match in which Mascherano equalled Javier Zanetti's all-time appearances record for Argentina (142 caps), fans ended up hoping that he won't be given the chance to take that record outright. Mascherano's move to Hebei Fortune in China was, he has said, motivated by a desire to return to playing in midfield. No offence to the level of the Chinese Super League, but even before the game it seemed generous on Sampaoli's part to allow him to do the same against a team as powerful as Spain. Mascherano's passing, once safe if rarely positive, is no longer even safe, and he showed none of the pace and mobility of old.

All over the field, all through the match, Argentina looked out of sorts against Spain. EPA/Rodrigo Jimenez

4. The midfield was all wrong

Mascherano wasn't the only thing wrong with Argentina's three-man midfield, though. Ever Banega, so impressive after coming off the bench against Italy days before, looked lost between the lines. Whether he operates better as one of the two in a 4-2-3-1 (the formation used against Italy) than he does in a midfield three is one of the questions Sampaoli will have to think long and hard about, because Banega -- on both form and simple lack of realistic alternatives -- surely has a place in the squad for Russia assured.

On Mascherano's other side, Lucas Biglia once again disappeared. He's shown in the past that he can play a role in Argentina's midfield, but it's normally as the most defensively minded player. Alongside Mascherano, he looked superfluous, his positioning not good enough to help with the job of shielding the defence, and his passing not zippy enough against Spain's enthusiastic press to contribute much going forward. At the top level, teams can't afford to carry one passenger, never mind three -- and least of all in the most important area of the pitch.

5. The centre-backs never woke up

Nicolas Otamendi went into this game as the undisputed first-choice option for Argentina at centre-back. The scary thing is that he probably still is, even after a display in which he and Marcos Rojo were either standing stock still or in an entirely different postal code for all four of Spain's second-half goals. Ezequiel Garay, an option Sampaoli would dearly love to be able to call upon, has asked not to be called up for international duty due to fitness issues, and as with central midfield, Argentina -- a nation once stacked with world-class options in the position -- doesn't have many other great choices here.

Rojo's inclusion so soon after returning from a long injury spell was clearly due to a desire to check him out as an option for the squad as well, and it went spectacularly wrong. Full-backs Fabricio Bustos and Nicolas Tagliafico didn't help, but it was Otamendi and Rojo who, when Spain's forwards rushed at them, seemed to just stand around like training cones.

6. Substitutions didn't turn the tide

Statistically, the game wasn't so one-sided. These thrashings often aren't; Spain scored six goals from six shots on target, and at half-time Argentina were still very much in the game, just 2-1 down. Why, then, did Sampaoli wait any longer before sending on Lautaro Martinez, Racing's young striker? Martinez is a player Sampaoli wanted to look at, but by the time he was sent on Spain had run in two further goals and Argentina looked utterly deflated.

Gonzalo Higuain had had very little service before, and so at 4-1 down, what hope was there that Martinez would get anything to even snatch at? The result is never the most important aspect of a friendly, but the scoreline affects the dynamic of the game, and on that basis all Argentina's outfield subs came too late for the manager to get a look at the players introduced in anything approaching a contest.