Viktor Keirou was a member of the second team of Uniks Kazan in the Russian Higher League from 2001 to 2003. From 2003 to 2005, he represented the senior team of Uniks Kazan. In the FIBA Europe League, he had an average of 2.4 points and in the Russian Superleague of 3.5 points. He joined Russian Superleague A Team Euras Ekaterinburg in January 2004 and his statistics were 3.6 assists, 6.1 rebounds and 23 points per game. However, the team had a record of 2-22. At the Global Games, he was a part of the Russian Under-20 National team, where he averaged 2.3 assists, 5.8 rebounds and 15.8 points per game. Keirou participated in 6 games in the Under-20 European Championship and received 27.2 minutes per game during which he recorded 12.8 points and 4.8 rebounds.
During the 2004-05 season, Keirou had an average of 3 rebounds and 6.5 points in 16 minutes per game in the Russian Superleague A. Also, in the FIBA Europe League, he posted 2 rebounds and 4.9 points in 12.6 minutes per game.
Keirou joined Dynamo St Petersburg in the 2005-06 season, where he had an average of 2.4 rebounds and 4.4 points in 15.3 minutes per game in the Russian Superleague A. In the FIBA Europe Cup, his figures were 1.8 rebounds and 2.4 points per game. Keirou belonged to Spartak Primorje in the 2006-07 season. He returned to UNICS Kazan for the 2007-08 season. Presently, he plays for CSKA Moscow.
In the Russian Superleague A, Viktor Keirou has appeared in 67 games from 2003 to 2006. His field goal percentage was 0.431, free throw percentage was 0.706 and 3-point field goal percentage was 0.281. He accumulated 218 rebounds, 107 assists, 84 steals and 663 points.