In the 2008–09 season, Leclaire injured his ankle, sidelining him for the season and the Blue Jackets promoted rookie Steve Mason. Mason's play was outstanding, leading the Western Conference in several categories. In a playoff race, the Blue Jackets traded Leclaire to the Ottawa Senators, along with a second-round pick in 2009 (Robin Lehner), in exchange for Antoine Vermette on deadline day March 4, 2009. As expected, Leclaire assumed the role of starting goaltender with the Senators in 2009–10, once he had fully recovered from ankle surgery. However, Leclaire would finish the season backing up Brian Elliott in the Ottawa net, due to inconsistent play and injuries - including a broken cheekbone suffered from being hit by an errant puck while sitting on the bench during a game. The inconsistency and injuries worsened considerably in 2010–11 with Leclaire playing 14 NHL games and the Senators finishing the year with a top-2 tandem of goaltenders other than those who started the season with the team. During the season he underwent hip surgery.