Favourite Spain began its campaign with a 4-1 win over Finland in the first game of a doubleheader, but had to respond to some early adversity after falling behind in the first minute.
Finland's Linda Sallstrom found the opener just 49 seconds into the contest with her right-foot strike back across the keeper into the bottom-left corner, but from that point on it was all Spain.
Spain controlled 79.3 per cent of the first-half possession, taking the game by the scruff of the neck, and was rewarded with an equaliser in the 26th minute from Irene Paredes.
Aitana Bonmati gave Spain a 2-1 lead in the 41st with a header from near the penalty spot, its half-time advantage well deserved after completing 294 passes compared to just 47 from Finland in the first 45 minutes.
The second half was even more dominant, with Spain attempting 20 shots to Finland's one, racking up 2.42 expected goals in the process.
Their dominance paid dividends in the 75th minute when Lucia Garcia finally gave the seventh-ranked team in the world some breathing room, before Mariona Caldentey put the icing on the cake deep into stoppage-time.
Germany then turned on the style in a 4-0 win over Denmark, with Lina Magull opening the scoring in the 21st minute after dispossessing one of the Danish defenders and powering her shot high into the top corner.
After striking the post twice in the first half, Germany opened the floodgates in the second.
Magull turned provider by assisting Lea Schuller to make it 2-0 in the 57th minute. It was the 24-year-old Schuller's 26th international goal from her 40th cap.
Lena Lattwein was brought off the bench in the 61st minute and got herself on the scoresheet 17 minutes later, getting on the end of a Lena Oberdorf assist to net Germany's third, before fellow substitute Alexandra Popp completed the rout in the 86th minute with a point-blank header from Sydney Lohmann's cross.
Germany and Spain's next fixture will be against each other on Wednesday (AEST), when Finland faces Denmark.