The 2017 gold medallists headed an all-Russian podium with Ksenia Stolbova and Fedor Klimov taking silver while Natalia Zabiiako and Alexander Enbert claimed bronze.
Tarasova’s fall in Wednesday’s short programme had left the pair — a couple both on and off the ice — languishing in fifth and seemingly with little hope of a podium, let alone a second successive title.
But they pulled a sweet success out of the bag in an immaculate free dance set to Candyman by Christine Aguilera which earned them a personal best 151.23 tally for a total score of 221.60.
The couple then had a nerve wracking time rink-side watching the six remaining pairs have a shot at them, with each missing the target.
Tarasova said: “Yesterday I made a big mistake, I got really mad at myself but today I was able to come out really strong.”
Morozov said performing in front of the home fans made the win even more special.
He then turned his thoughts to next month’s Olympic Games.
“We were already confident (about Pyeongchang), and this will motivate us further to do our very best.”
While the home team celebrated there was heartache for French duo Vanessa James and Morgan Cipres.
They led the pack after Wednesday’s short programme to conjure up real hope of claiming the title for France for the first time in 86 years, but in the end had to settle for fourth.
James and Cipres were last to go and did nothing wrong in their dance to Sense of Freedom by Maxime Rodriguez but the judges were not overly impressed, awarding them a score of 134.64, well below their personal best of 146.87.
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