Russian figure skater Kamila Valiyeva and her coach Eteri Tutberidze are seen after the performance in the women’s free skating program on Feb. 17. (Sergei Bobylev/TASS/Getty Images)Russian figure skater Kamila Valieva placed fourth in the women’s figure skating final at the Beijing Winter Olympics on Thursday, capping off more than a week of controversy after the teen was cleared to skate despite testing positive for a banned substance.Valieva was tipped for gold in the event but fell numerous times during her free skate routine. Standing by the 15-year-old was her coach, on whom the spotlight now falls.Coach in the spotlight: At the center of the controversy — and the Russian skating world — is Valieva’s coach, Eteri Tutberidze.Frequently called the most powerful woman in figure skating, Tutberidze is the driving force behind Russia’s dominance in the sport. Her studio in Moscow attracts the best female figure skaters from around Russia, who are trained from an early age to break records and perform dazzlingly complex jumps, multiple coaches and skaters told CNN.Valieva made history last week by becoming the first woman to land a quad at the Olympics, and recent female Russian skaters have been known for pushing boundaries on the tricks they can do, from triple axels to triple flips and other difficult combinations.”We are absolutely sure that Kamila is innocent and clean,” Tutberidze told Russian TV last week.Tutberidze is also infamous for her brutal training regimens: In a December interview with Russian TV, she said her skaters train 12 hours a day, saying they can “always do more, demand more from yourself.”The coach has trained a string of Olympic medalists, but scrutiny has also been cast on how her best protégées have had short-lived careers.CNN has reached out to the Russian Olympic Committee (ROC) for comment from Tutberidze and ROC team doctor Filipp Shvetsky on the points raised in this story but has not received a response.Read the full story: