Question: Name the Russian mixed martial artist who currently fights in the lightweight division of the UFC and is a training partner of Natalia Vitalyevna Vorobieva, a Russian wrestler who competed in the 2012 Summer Olympics?

Context articles: Islam Makhachev
Akop Stepanyan
Alexander Sarnavskiy
Chris Gruetzemacher
Natalia Vorobieva
Albert Tumenov
Gadzhimurad Antigulov
Khabib Nurmagomedov
Jens Pulver
Caol Uno

Islam Ramazanovich Makhachev (Russian: Ислам Рамазанович Махачев ; born October 27, 1991 in Dagestan) is a Russian mixed martial artist, judoka and sambist of Lak origin.
 He is a Combat Sambo World Champion, and currently fights in the lightweight division of the Ultimate Fighting Championship.
Akop Stepanyan (Russian: Акоп Степанян , Armenian: Հակոբ Ստեփանյան ; born May 6, 1986) is a Russian mixed martial artist of Armenian heritage who competed in the featherweight and lightweight division for the Bellator Fighting Championships.
 He is currently fights in the lightweight division of the Absolute Championship Berkut.
Alexander Sarnavskiy (born January 17, 1989) is an Ethnic Russian mixed martial artist who competes in the lightweight division.
 A professional MMA competitor since 2008, Sarnavskiy has mostly competed in his native Russia, where he is an M-1 Global veteran and former lightweight division in the Bellator Fighting Championships.
 Alexander is currently ranked as the #4 lightweight in Europe.
Chris "Gritz" Gruetzemacher (born June 16, 1986) is an American mixed martial artist who competed in the UFC TV series The Ultimate Fighter series 22 (TUF 22).
 Gruetzemacher was the former fighter for Strikeforce and World Series of Fighting (WSOF) and he currently fights in lightweight division in the Ultimate Fighting Championship (UFC).
Natalia Vitalyevna Vorobieva (Russian: Наталья Витальевна Воробьёва ; born 27 May 1991 in Tulun, Irkutsk oblast, Russian SFSR, Soviet Union) is a Russian wrestler, who competed at the 2012 Summer Olympics.
 Vorobieva reached the finals in the 72 kg category where she beat Stanka Zlateva of Bulgaria to win the gold medal.
 She is also the holder of a number of titles at the youth levels.
 In the 2015 Golden Grand Prix Ivan Yarygin final match, Vorobyeva defeated Ochirbatyn Nasanburmaa of Mongolia.
 Vorobyeva train with UFC and M-1 Global MMA fighters, such as Khabib Nurmagomedov, Islam Makhachev, Vyacheslav Vasilevsky, Abubakar Nurmagomedov, Mikhail Malyutin, Ali Bagov.
Albert Khuseinovich Tumenov (Russian: Альберт Туменов ; Karachay-Balkar: Альберт Туменланы ; born December 26, 1991 in Kabardino-Balkaria) is a Russian mixed martial artist and former amateur boxer of Balkar heritage.
 Since 2014, he competed in the welterweight division of the Ultimate Fighting Championship.
 As of March 8, 2016, he is ranked #13 in official UFC welterweight rankings.
 Tumenov is currently fights in the welterweight division of the Absolute Championship Berkut.
Gadzhimurad Antigualov (Russian: Гаджимурад Антигулов ; born January 1, 1989) is a Russian mixed martial artist of Avar heritage who currently fights in Light Heavyweight division in the Ultimate Fighting Championship (UFC).
 He was the two times Light Heavyweight champion for Absolute Championship Berkut.
 He is currently the #15 ranked light heavyweight in UFC rankings as of 2 July 2017.
Khabib Abdulmanapovich Nurmagomedov (Russian: Хабиб Абдулманапович Нурмагомедов ; Avar: ХIабиб ГӀабдулманапил НурмухӀамадов ; born September 20, 1988) is an undefeated Russian mixed martial artist of Avar heritage.
 He is a two time Combat Sambo World Champion, a wrestler and a judo black belt who currently fights in the Lightweight division of the Ultimate Fighting Championship.
 He currently holds one of the longest undefeated streaks in MMA with 24 wins.
 As of 17 November 2016, he is ranked the #1 contender in the UFC Lightweight division and #12 in official UFC pound-for-pound rankings and numerous other publications.
Jens Johnnie Pulver (born December 6, 1974) is an American professional mixed martial artist and undefeated boxer and kickboxer.
 Pulver was the inaugural UFC Lightweight Champion in addition to serving as the head coach on "The Ultimate Fighter 5" reality show against long-time rival B.J. Penn.
 In mixed martial arts, Pulver competed at the Lightweight, Featherweight, Bantamweight and Flyweight divisions in addition to competing at the Middleweight, Light Middleweight, and Welterweight divisions as a professional boxer.
 While perhaps best known for competing in the UFC, Pulver has also competed in Pride Fighting Championships, for the PRIDE 2005 Lightweight Grand Prix.
 He is to-date the youngest UFC Lightweight Champion in the UFC history, eventually relinquishing his title, after two defenses, due to a contract dispute.
 Pulver officially retired from combat sports in 2014.
 Pulver is considered the founder of the UFC lightweight division.
Kaoru "Caol" Uno (宇野薫 , Uno Kaoru ) (born May 8, 1975) is a Japanese mixed martial artist.
 He is the Co-Champion of the UFC 41 Lightweight Tournament and a former Shooto Lightweight Champion.
 As one of the early Ultimate Fighting Championship's elite Lightweight competitors, Uno competed for the UFC Lightweight Championship on two separate occasions.
 Despite falling short in both championship bouts; losing a five-round decision against Jens Pulver at UFC 30, to determine the inaugural UFC Lightweight Champion as well as a draw against B.J. Penn at UFC 41 (in a bout which would have determined the new UFC Lightweight Champion and UFC 41 Lightweight Tournament Winner), Uno is acknowledged as a pioneer for his impact and influence during the early era of the UFC Lightweight Division.