Two UFC newcomers, including a Russian champion, will make their debuts on short notice at UFC on ESPN+ 15 in Shenzhen, China.

On the main card, undefeated M-1 Challenge light heavyweight champ Khadis Ibragimov (8-0 MMA, 0-0 UFC) will step in to take on Da Un Jung (11-2 MMA, 0-0 UFC). Jung was originally slated to take on Jamahal Hill, before visa issues forced the American out of the bout.

On the prelims, Movsar Evloev (11-0 MMA, 1-0 UFC) will now take on Zhenhong Lu (18-6 MMA, 0-0 UFC) in a rematch of their June 2015 clash. At M-1 Challenge 58, Evloev defeated Lu via unanimous decision. The former M-1 Challenge champ Evloev was scheduled to fight Mike Grundy, but the United Kingdom based fighter was forced off the card due to injury.

A person with knowledge of the situation confirmed both bookings with MMA Junkie. The person asked to remain anonymous because the UFC has yet to make a formal announcement. Both fights were first reported by Russian social media account Red Fury MMA.

Ibragimov, 24, signed with the UFC earlier this year via the M-1 Global/UFC partnership deal. The deal allows M-1 champions an out clause if the UFC becomes interested in signing them. The Dagestan-born fighter Ibragimov has won his last five outings via stoppage. In his most recent fight in March, Ibragimov finished then-undefeated Rafal Kijanczuk via strikes at M-1 Challenge 101.

China’s Lu will be making his promotional debut in his home country. Lu has won eleven of his last twelve bouts with eight finishes in that stretch. While he has primarily competed for the WLF W.A.R.S. promotion, he’s also fought under other notable Asian promotional banners including Kunlun Fight and Rebel FC.

UFC on ESPN+ 15 will take place Aug. 31 at the Universiade Sports Center. The main card will stream live on ESPN+ after prelims on ESPN.