Pole position was decided in the closing seconds, with Rosberg taking pole from his team mate Lewis Hamilton.
Both drivers pushed hard in challenging conditions to progress through into Q2, as the track dried however, neither driver was able to get a clean lap to get the maximum out of the FW35 on the supersoft tyres.
Jean-Eric Vergne: "Anything can happen on this track so we can definitely aim for points tomorrow."
Dr Vijay Mallya: "...for Paul (Di Resta), I would like to apologise to him because we did not get the tyre strategy right during Q1"
Felipe Massa had to watch the qualifying session from the pits, after the accident in this morning’s free practice.
Pole position is Nico's third in a row and the fourth consecutive pole for the team in the 2013 season.
Sergio Perez: “Anything can happen at Monaco on Sunday.”
On course for a two-stop race
Mark Webber set the fastest lap for the team in Thursday practice on the streets of Monte Carlo.
Vodafone McLaren Mercedes: “We need to give it our all on Saturday”
Scuderia Toro Rosso's Jean-Eric Vergne and Daniel Ricciardo
Objectives: Aero evaluations, set-up work and tyre testing.
Nico's fastest time in the afternoon session was one second quicker than the fastest lap in P2 last year