The Moscow crowd enjoyed an entirely Russian podium in the pairs free skating event as Tarasova and Morozov scored an impressive 221.60 points, over 10 points clear of fellow Russians Ksenia Stolbova and Fedor Klimov.
And it was Natalia Zabiiako and Alexander Enbert who completed the all-Russian podium as they just edged out French pairing Vanessa James and Moran Cipres by 0.01 of a point in a dramatic finale.
Elsewhere, it was a day to remember for Alina Zagitova who leads the ladies' short programme following a fine day on the ice.
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The Russian, who is making her debut at the competition in Russia's capital, nailed all her jumps, including a fast triple lutz-triple loop combination.
The debutant scored an impressive 80.27 points for her performance, more than 1.5 points ahead of Russian teammate and two-time world champion Evgenia Medvedeva.
Zagitova said: "It's my first Europeans, but I was able to calm down and I was able to show what I have worked on with my coaches.
"I am very pleased to have finally skated a clean short program. Since the Russian Nationals I've been focusing on consistency in practice and on polishing all elements."
Medvedeva, who sat out the Grand Prix Final and Russian nationals to recover from a cracked metatarsal, finished just ahead of Italian Carolina Kostner, who placed third with a score of 78.3.
"I've been longing to come back to the ice and compete," Medvedeva said. "I'm not happy with the skate but there's time for me to tighten it up before PyeongChang."