Who is the oldest player who played for Avangard Omsk during the regular season in 2000-2001?
oldest player refers to MIN(birthdate); Avangard Omsk refers to TEAM = 'Avangard Omsk'; regular season refers to GAMETYPE = 'Regular Season'; 2000-2001 season refers to SEASON = '2000-2001';

SELECT T2.PlayerName FROM SeasonStatus AS T1 INNER JOIN PlayerInfo AS T2 ON T1.ELITEID = T2.ELITEID WHERE T1.SEASON = '2000-2001' AND T1.GAMETYPE = 'Regular Season' AND T1.TEAM = 'Avangard Omsk' ORDER BY T2.birthdate ASC LIMIT 1