The veteran goalie on Friday signed a one-year, $1-million deal to back-up starter Craig Anderson.
"There's obviously familiarity in the team and with the city and the relationship with Bryan dates back to when I was drafted by the Panthers in '99," Auld said during a conference call after the signing.
"At the end of the day, it just made the most sense."
Auld faced the rebuilding Senators toward the end of the regular season, losing in overtime to a group of largely "unknown" players.
"It's a group of guys that work hard and that's exciting," he said.
Auld, who has played with Florida, Vancouver, Phoenix, Boston, Dallas, New York and Montreal.
The 30-year-old played 16 games for Montreal in 2010-11, going 6-2-2 with a 2.64 goals against average. In 223 career games he's 89-84-2-28 with a 2.77 GAA.
With files from The Canadian Press
