Despite holding a comfortable advantage over Red Bull in the standings, Nico Rosberg says Mercedes need to become "bulletproof" to keep the Bulls at bay.
Last season in Montreal, Mercedes suffered their very first defeat of the year when Daniel Ricciardo took the chequered flag.
The Aussie, though, was helped on his way to victory by reliability issues for the Mercedes pairing.
Both suffered a drop in power with Lewis Hamilton's ERS issues playing a role in his brake failure, while Rosberg's meant he was caught - and eventually overtaken - by Ricciardo.
The German said: "We need to make sure that we're bulletproof.
"Having lost the win, that's very, very disappointing, definitely, and also disappointing for us as a team.
"We have such speed and such a great car, to not win the race and even just finish with one car and come second is hugely disappointing for us, definitely.
"Our ambition is to finish one-two so we need to make sure that we get back there again next race in Austria."
However, it is not just reliability that Mercedes must work on with the Championship leader admitting they need to continue to develop the car to keep the Bulls at bay.
"We are fully aware that Red Bull is still an amazingly strong team and pushing like crazy to catch us.
"We are well aware of that and we are always concerned and always making sure that our drive remains exactly the same as it was last year when we were half-a-second behind them.
"We're really pushing to even extend the gap."