Spain saw off Switzerland in a drab encounter at the Alfredo Di Stefano stadium in Madrid to consolidate pole position in the group.
Mikel Oyarzabal scored the only goal of the game as the Real Sociedad star pounced on a mistake from Swiss custodian Yannick Sommer.
The visitors struggled to claw their way back into the match thereafter, though La Roja barely threatened the Gladbach 'keeper again despite creating numerous chances.
Here are the major talking points from the match:
#1 Spain lacked a natural goalscorer
As expected, La Roja kept the lion's share of the ball, ending the game with 60% possession and even using it efficiently by creating numerous chances.
Yet, they managed just two shots on target out of 12 attempted and barely troubled Yannick Sommer in the second half. Could this be due to the lack of a natural goalscorer?
Luis Enrique opted for quite an unconventional formation here, going with a four-pronged attack of Ansu Fati, Daniel Olmo, and Ferran Torres behind the lone striker Mikel Oyarzabal.
And even though the Real Sociedad man did score, he's a winger by trade, not a number 9, like Gerard Moreno and Rodrigo Moreno. But having left them both on the bench, the ex-Barcelona manager doesn't appear convinced with his striking options either.
The lack of goals has been a concern for Spain of late, scoring more than once in a match on just one occasion now from the last four outings.
#2 Merino shines in midfield
Even though Spain were struggling to get their act together in attack, there were no such issues in midfield as Mikel Merino impressed playing alongside Sergio Busquets.
The Real Sociedad star brought so much craft and guile to his side, leading La Roja's press from the centre of the pitch and also forcing an error from the Swiss defense which lead to the winner.
He also laid on the joint highest number of key passes and was crucial to the defense too, making two tackles and interceptions. Importantly, he also won back possession 14 times - also the highest by any player in the match.
This was only his fourth game for the Reds and just his second start.
Should he continue in the same vein of form, the position next to Busquets could be nailed down by the former Newcastle man.
#3 Sommer paid the price for his mistake
For all his heroics with Borussia Monchengladbach in the Bundesliga, the fact is that Yannick Sommer remains underrated. He's made some excellent saves in the past and shown quick reflexes too, whilst also keeping 21 clean sheets in the top-flight in the last two seasons.
He was once again sound in goal for the Swiss, but not before slipping up with a poor pass that would prove costly for them.
After receiving a back pass, Sommer, under pressure from Oyarzabal, played the ball straight to Merino, who then cut it back for his Real Sociedad teammate to lash one into the bottom corner.
A lapse in concentration and the Swiss custodian was quickly punished for it. Given how Spain was struggling to hit the broadside of the banjo for the rest of the match, Sommer was left to rue what might have been.
#4 What's happened to Switzerland's attacking might?
Switzerland's impressive record in the Nations League's maiden edition and the recent Euro qualifiers was down to its free-scoring nature, taking apart every team on its way.
The Rossocrociati scored 15 times from just five games in this competition, followed by another 19 goals in the qualifying campaign. But now, they are struggling to replicate their goal scoring exploits.
That's cause for concern to Vladimir Petkovic's side, who're now languishing at the bottom of League A Group 4, having scored only twice from three games. And against Spain, far from finding the net, the Swiss managed just one shot on target all night!
The goals have visibly dried up, and it's coming back to haunt them. Even though Spain weren't exactly menacing either, the fact that Switzerland barely threatened is worrisome.
Unless they finds their attacking rhythm again and start firing on all cylinders, the Central European side could end up getting relegated into League B.
#5 Spain edge closer to knockouts
It's no secret that Spain isn't the force that it used to be until 2012 and despite seeing an influx of new and talented youngsters in the squad, they have struggled to make an impression on the big stage.
The former world and European champions have been knocked out in the round of 16 from each of the last two major tournaments, whilst also finishing behind England in the group in the UEFA Nations League last year.
Having made a strong start this time - winning twice and drawing once from three games - the Reds have a chance to make a statement again by qualifying for the semi-finals.
With Germany still in decline, and Ukraine and Switzerland not offering anything by way of a realistic challenge, the path should be relatively clear for Spain to progress.
They do have a few shortcomings - such as the lack of a clinical striker as we saw earlier - but even then, La Roja look primed to finish as group leaders.