The first matches were played in Group B yesterday, and the marquee event was Spain/Holland, a rematch of the dour 2010 final won in extra time by Spain. That meeting was a contrast in styles, with the elegant Spanish tika-taka dance countered by a thuggish Dutch response that merited (but did not receive) two red cards in the opening minutes. It was hard to watch and unless you were a Spain supporter who was just happy to win, it was a thorough disappointment.

Yesterday? Not so much: The Netherlands destroyed Spain 5-1. Their performance not only rendered tiki-taka ineffective - for a significant portion of the match it was difficult to even detect its presence on the pitch.

I've been saying for two or three years that Pep Guardiola was getting too much credit. He didn't invent tiki-taka, but a quick review of the hardware case at Camp Nou lends support for those who'd argue that he perfected it. And it was during these years when Spain earned its greatest international success ever, winning two European Championships and the 2010 World Cup. Those teams were built around Pep's men at Barca and deployed Vicente Del Bosque's version of tiki-taka.

So great was Guardiola's success that tiki-taka became the system to emulate. Pep became the manager that the great clubs coveted. Especially, it must be said, West London's Chelsea FC. Owner Roman Abramovich's fevered pursuit of Pep bordered on stalking.

Yes, Barca was amazing. But not because of Guardiola. They were amazing because of a perfect storm, a golden generation, a once-in-a-lifetime (if that) alignment of the stars: Xavi and Andres Iniesta, the dynamic midfield engine without whom Spain and Barca might well have combined to win zero trophies. It was kind of like the futbol equivalent of Pat Riley and the showtime Lakers: his greatest genius was naming Magic, Worthy and Kareem in the starting lineup.

The test of Guardiola's genius was going to be this: what could he accomplish without Xavi and Iniesta? Same for Del Bosque - what would happen to the famed tiki-taka system once its talismans aged out of their prime?

Well, now perhaps we're finding out. Iniesta is 30 and Xavi 34, and both have turned onto the back nine of their glorious careers. Yesterday's game? The two most important players in the world over the past six years might as well have been in witness protection. Holland's theory was familiar enough for those of us who have studied tiki-taka's occasional misfires in recent years: lock down the middle of the field, clog up the channels where Xavi and Iniesta like to operate, pray for a turnover and counter-attack like your hair is on fire if you get the ball. But gods, Louis van Gaal's side executed it to perfection.

In fact, this understates the result. Holland wasn't simply parking the bus. They pressured higher in the midfield and while Spain still dominated possession (58%) the Dutch used their time on the ball with great attacking intent. They scored five, and you might well argue that they could have had at least three more.

In other words, Holland simply shut Xavi and Iniesta down, and they did so in ways that we have rarely seen before, ways that would have been unimaginable for a younger Dynamic Duo.

Meanwhile, Pep won the Bundesliga with Bayern Munich, thanks largely to the best assemblage of talent in football. But how did der tiki-taka look when it hit Real Madrid, a team with exceptional talent of its own, in the Champions League semifinals? A 5-0 loss on aggregate, including a 4-0 nard-stomping on home soil. In a nutshell, the famed Guardiola and his indomitable tiki-taka system underperformed arguably the strongest roster on the planet.

We sports fans all have opinions. And I've been wrong before. And advanced metrics do support the theory that possession - the heart and soul of tiki-taka - is a strong indicator of success. And Xavi, Iniesta, Spain, Barca, Bayern and Guardiola, all are still alive and there's plenty of opportunity to prove me wrong.

But where the argument is that Pep Guardiola has been getting a lot of credit that he doesn't deserve, yesterday's Spain result and the UCL semifinal seem, at the very least, like a couple of data points that are consistent with the theory.

I hope everybody appreciated Xavi and Iniesta in their prime. They made a lot of folks look better than they're ever going to look again.