Mitrofanov was born on June 12, 1997, in Madison, Wisconsin.[1] He is the eldest of two children born to Yelena, a real estate agent, and Gennadiy, a natural gas and oil marketer.[2] He has a sister, Nina.[2] After graduating (in May 2016) from Spring Creek Academy in Plano, Texas, he began studying sports medicine at the University of Texas at Dallas.[2] He earned a bachelor's degree in healthcare studies in 2023.[3] Mitrofanov has expressed interest in opening his own mechanic shop after finishing his competitive figure skating career.[3]
Career
Early years
Mitrofanov began learning to skate in 2001 at the age of four after doctors encouraged his parents to enter him into sports as a way to improve the weak immune system he had been born with.[1][3] He was coached by Alexei Mantsorov from 2005 to 2014.[2] Skating in the novice pairs' category, he placed 8th at the 2015 U.S. Championships with Emily Chan, and 6th at the 2016 U.S. Championships with Ashlee Raymond.
Partnership with Lu
2016–17 season
Mitrofanov teamed up with Audrey Lu in May 2016.[4] Making their international debut, the pair placed 12th at an ISU Junior Grand Prix (JGP) event in the Czech Republic in September 2016. Their season came to an end in November, after Mitrofanov dislocated his shoulder at the Midwestern Sectional Championships.[4] He underwent shoulder surgery and resumed training after six months.[4]
2017–18 season
Lu/Mitrofanov placed 5th at both of their JGP assignments. In January, they won the junior pairs' title at the 2018 U.S. Championships; they ranked first in both segments and outscored the silver medalists by 17.74 points. In March, the pair placed 5th (6th in the short program, 4th in the free skate) at the 2018 World Junior Championships in Sofia, Bulgaria.
With the COVID-19 pandemic affecting international travel, Lu/Mitrofanov were assigned to attend the 2020 Skate America, the Grand Prix having been arranged primarily based on training location.[7] They placed third in the short program, 3.31 points ahead of national pewter medalists Cain-Gribble/LeDuc.[8] Coming fourth in the free skate, their lead from the short program was nevertheless enough to remain in third place overall, winning the bronze medal.[9]
Competing at the 2021 U.S. Championships, Lu/Mitrofanov placed third in the short program with a clean skate.[10] They were fourth in the free skate, dropping to fourth place overall and winning the pewter medal.[11]
2021–22 season
After beginning the season with some minor America competitions, Lu/Mitrofanov competed on the Grand Prix at the 2021 NHK Trophy, finishing in fifth place.[12] They went on to finish in fourth at the 2021 Rostelecom Cup, after which Lu said they were "satisfied" with the results on the Grand Prix that year.[13] They next competed at the 2021 CS Golden Spin of Zagreb, where they won the gold medal, their first Challenger title.[14]
Lu/Mitrofanov won the bronze medal at the 2022 U.S. Championships. Mitrofanov said they were "very happy and grateful" for the event and its large audience.[15] As a result of their placement, they were assigned to compete at the 2022 Four Continents Championships in Tallinn, and named second alternates to the American Olympic team. Lu/Mitrofanov won both segments of the Four Continents competition to take the gold medal.[16]
Mitrofanov briefly skated with Hazel Collier for the ice show, An Evening with Champions.[17]
Partnership with Efimova
2023–24 season
Upon learning about her split with previous partner, Ruben Blommaert, Mitrofanov, messaged Finnish-Russian pair skater, Alisa Efimova on Instagram, asking if she would be interested in having a pair skating tryout with him. Efimova went on to contact Mitrofanov's longtime coaches, Aleksey Letov and Olga Ganicheva, asking if they would be interested in coaching her, to which they agreed. Following a successful tryout, Efimova moved to Norwood, Massachusetts, to train at the Skating Club of Boston with Mitrofanov. It was announced in June 2023 that the pair team would represent the United States.[18][19]
Following a silver medal win at the domestic U.S. Pairs Final, Efimova and Mitrofanov qualified for the 2024 U.S. National Championships.[20] At the event, the pair placed fifth in the short program, but won the free skate, allowing them to move up to second place overall.[21]