2009-10: Gusev played for the CSKA-Red Army junior team in Russia. He scored 17 goals with 40 goals and had 14 penalty minutes in 48 games. In five playoff games he scored 1 goal with 2 assists.
2010-11: Gusev made his KHL debut, skating in 18 games for CSKA-Red Army, and was the leading scorer for CSKA-Red Army's junior team. Gusev scored 1 goal and was minus-one with 8 penalty minutes in limited ice time with the KHL club. In 38 junior games he scored 22 goals and was plus-35 with 37 assists and 14 penalty minutes. CSKA-Red Army captured the MHL championship and in 16 playoff games Gusev scored 17 goals with 10 assists and was plus-15 with 6 penalty minutes. Gusev was ranked 52nd by Central Scouting in their final rankings prior to the 2011 NHL Draft but was not selected.
2011-12: Gusev appeared in 15 KHL games for CSKA-Red Army and was the MHL junior league's second-leading scorer. He represented Russia at the 2012 U20 World Junior Championship. Gusev scored 2 goals with 1 assist and was minus-two in KHL play. In 34 games for CSKA-Red Army's junior team he scored 30 goals with 46 assists and was plus-23 with 26 penalty minutes. Gusev scored 3 goals with 6 assists and was plus-6in seven games for Russia at the WJC. Russia won a silver medal at the tournament. Gusev was ranked 20th amongst European skaters in Central Scouting's final rankings prior to the 2012 NHL Draft.