|Michaela Stejskalová and ZVVZ USK Prague stepped on the gas to deny Rivas|
The guard stood out as the Czech champions eventually strolled to victory on their home floor, even if it took quite some time for them to get going after a lacklustre opening.
Rivas started brightly and sensed a potential shock during the early exchanges when a basket by Jasmine Hassell put them 18-9 in front.
They still led 20-13 heading into the second quarter, but it was all downhill for the visitors from this point onwards.
Prague firstly got level at 25-25 via a jump shot from Ilona Burgrova and then proceeded to take complete control for the remainder of the contest.
They cranked up their offensive game during the middle two quarters and poured in 53 points, before hammering the final nail into the visitors' coffin with a 7-0 start to the last period.
Short-handed in the backcourt, Rivas had no answer to the depth of Prague and were swept aside, with Burgrova having a superb shooting night and finishing with a six of seven floor shooting performance en-route to 12 points.
Jelena Dubljevic and Kia Vaughn also had a good night in the paint, with the former amassing 16 points and Vaughn foraging 11 rebounds.
Rachel Allison claimed a creditable 14 points, seven rebounds and five assists for Rivas, who at least won the last quarter to possibly carry some momentum into game two.
Coach Natália Hejková, ZVVZ USK Praha:
"I trusted my team despite the first half [showing]. It is very important to win the home games in the play-offs and our players knew it very well. That is why they were so nervous at the beginning. But we won and that is important."
Coach Jose Ignacio Hernandez, Rivas Ecopolis
"We didn´t play well in the second and third quarter. My team didn´t fight as usual and I didn´t like it. Now it is important to concentrate on Friday's game. Prague played a fantastic game."
Frida Eldebring, Rivas Ecopolis:
"It was a tough game. USK Prague played a good game, especially in the second half. They did a good job. Hopefully we can do better in the next game."
Ilona Burgrová, ZVVZ USK Praha:
"Today´s game was the most important game of the season. We all played as a team. It was a great game. But it is only a little step forward."