Heart attack.
What a loss.
Montreal 1985 was my first World Championships. For 10 days I videotaped MAG for FIG. Mostly Floor Exercise.
For us Li Ning and Tong Fei were the sensations. But the Soviet team was deep, deep:
Vladimir Artemov
Yuri Korolev
Valentin Mogilny
Yury Balabanov
Aleksei Tikhonkikh
Aleksandr Tumilovich
Korolev won the AA in Montreal as well as at Worlds 1981 Moscow.
A class champion. What a loss.
With a total of 34 individual medals at World Championships, World Cups, and European Championships competitions, Korolyov has more such medals than any other non-Olympian with Valentin Mogilny (17) being the next highest in this sort of medal count.
Gymnastics Coaching.com 
So sad that so many of these great champions die early. We have lost Balabanov, Mogilny and Korolev so far.
Artemov had a serious stroke last year but is recovering well.
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