After the 2007–08 season, Kadri was traded to the London Knights (his hometown team) in exchange for several draft picks. He played in 56 games for the Knights in 2008–09, recording 25 goals and 53 assists (78 points). Kadri was sidelined during the 2008–09 season when he suffered a broken jaw. He was selected to play for Team OHL in the ADT Canada Russia Challenge, but was unable to participate due to the jaw injury. Kadri was later invited to the Canada men's national junior ice hockey team's selection camp for the 2009 World Junior Championships but did not make the final roster. Also during the 2008–09 season, Kadri was chosen to play in the OHL All-Star Classic, where he suited-up for the Western Conference and scored one goal.