Australian Tops-Alexander, who came second in the Top 10 on Friday night, claimed victory with baffling ease to climb to 10th in the provisional rankings.
Alvarez Moya meanwhile, having admitted he did not ride well last time out in Paris, took no risks with his wife Marta Ortega‘s horse Carlo 273 and reaped the benefits of his caution.
There was also a great performance from Hans-Dieter Dreher with Magnus Romeo, a horse well known for being difficult yet one which the German handles expertly.
The Swiss crowd were also treated to an impressive performance from rising Swiss star Janika Sprunger. Riding Palloubet d'Halong - a "phenomenon" according to the 25-year-old - Sprunger registered the slowest double clear round with stunning style.
"Palloubet is only nine years old but he is an amazing horse," she said. "I am very happy to have him, we improve together, and we still need to gain experience to win a Grand prix."
Next up is the CSI5* in La Coruña, where Sergio Alvarez Moya and his wife will welcome some of the best riders in the world, including Steve Guerdat, the Olympic champion.