He will still have to go back each year for three weeks of military service that is mandatory for Swiss men, but for the next two years at least he knows he will be an NHL player the rest of the time.
The 26-year-old who played for Switzerland at the 2010 Winter Olympics turned a promising rookie campaign into a two-year deal with the Canadiens. It is a one-way contract worth US$1.2 million in its first season and $1.25 million in 2013-14.
The deal all but guarantees he will stay with the NHL club.
He was on a two-way deal, which includes a separate salary for time spent in the minor leagues, when he posted three goals and 13 assists in 59 games as an NHL rookie in 2011-12. His 102 shots ranked third among first-year rearguards.
''Last year I didn't know which way it would go and now I'm a lot more comfortable,'' Diaz said. ''I want to learn new things and show them on the ice.''
He was on the NHL all-rookie team at the all-star game last season as a replacement for injured defenceman Adam Larsson.
The five-foot-11 195-pound Diaz has fully recovered from the groin injury that put him out for the last 16 games of the season.
While more of a skilled player than a banger, he is looking forward to working under new Canadiens coach Michel Therrien, who likes physical hockey.
''I heard he's a coach who practises hard and wants to play hard in games. I think that's good for our team,'' said Diaz, who signed as a free agent with Montreal in 2011.
He averaged 18 minutes of ice time per game as a rookie. Due to injuries spent some time as a top-4 defenceman. Now he is expected to step up his game with a year of NHL experience behind him.
''It's hard to say where they see me,'' he sad. ''I'll give everything in camp and then it's the coaches' decision.''
While military service sounds daunting, Diaz said it was more like a holiday. Elite athletes in Switzerland are sent to a civilian centre in the mountains where they spend most of their time training for their sport.
He was with fellow athletes like forward Damian Brunner, who recently signed with the Detroit Red Wings, and 2007 skiing world champion Daniel Albrecht.
''They have everything there — a synthetic ice surface, bikes,'' he said. ''It's not for the military, but they use it.''
Diaz did his 18 weeks of boot camp when he was 19, and will have to go back for three weeks each summer until he is 30.
He also cleared up confusion about how his given name is spelled. On the Swiss national team he is Rafael Diaz, which is how he and his Spanish father spell it. But it is spelled Raphael on his passport, so that's his official name.
''It's a good question. I don't know why,'' he said.