The 21-year-old Gazprom Academy graduate made his first team debut in September 2017 against Ufa. In the 2017/18 season, he played twice more, in the Russian Cup against Dynamo St. Petersburg and in the RPL against Akhmat Grozny. 

Kaplenko is a Zenit-2 regular having appeared for the team 32 times in the FNL and 16 times in the PFL.