Korolev’s fall out of Top 100 was caused by an elbow injury which has been carrying ever since. He has been playing through the injury and has failed to come back to his former heights. After 2014 he fell out of the Top 500, and didn’t play for 7 months, until May of 2015. The Kazakh played only 4 tournaments, never winning 2 matches in a row. He has tried to qualify for Challengers in Furth and Prague, losing both in the first round. In July, Korolev won his first match after 9 months in the qualifying for the Atlanta 250, beating the unranked Antonio Ruiz-Rosales of Mexico in the third set tiebreak. He got routinely beat a round later by Austin Krajicek 6-3 6-3. His last tournament played was the $15,000 Futures in Mansfield, Texas. Korolev defeated Kaichi Uchida in the first round, only to fall to 17-years-old at the time Michael Mmoh.
Korolev is now ranked No. 1756 in the World. This ranking won’t even get him seeded in the qualifying of Futures tournaments. An interesting thing to notice is that Korolev decided to switch nationalities from Kazakhstan to Russia, where he was born. Right now, Korolev is in the entry lists for the USA F14 and F15 Futures, played on green clay in Orange Park and Vero Beach, both in Florida. One could presume that he will also enter USA F16 which is played in Florida as well. It will be very intriguing seeing this former Top 50 player make his way to the futures, and if he will ever get back on the ATP level.