Giordano appeared in 58 games for the Flames and scored 19 points before a shoulder injury ended his season. He required surgery to repair the damage suffered in a game against the Minnesota Wild. He recovered in time to begin the 2009–10 season, but several new additions to Calgary's defensive corps left him concerned about his position with the team. Instead, he solidified his place on the roster with a career year; Giordano set personal highs in goals (11), points (30) and was +17 for the Flames. "The Hockey News" named him one of the most underrated players in the league, and he was invited to join Team Canada at the 2010 IIHF World Championship. Giordano led the team's defencemen with three goals in the tournament and added an assist in seven games.