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
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.