Keep the Peace has captured the New Zealand Oaks in a breathtaking finish at Trentham to land a notable classic double for trainer Shaun Ritchie who recently claimed the NZ Derby with Military Move.

The Keeper filly, ridden quietly midfield by Opie Bosson, burst from the pack midway down the long straight and looked to be an easy winner, heading the big field by two lengths 100 metres from the post.

But November Rain and Zabeel filly Zarzuela, the race favourite, staged amazing late-finish runs to all but overhaul the leader.

They closed swiftly and in a blanket finish Keep The Peace got the victory by the slimmest of margins from November Rain who edged Zarzuela into third.

Two weeks ago Ritchie and Bosson combined at Ellerslie for the Derby with Ritchie now only the third trainer to win both races in the same season since the rationalisation of the classics in the 1970s.

Colin Jillings scored with the superb Uncle Remus, and Anthenaia in the 1977-78 season and Paul O'Sullivan with Popsy and Snaps in 1993-94.

Bosson got the Oaks ride on Keep The Peace after regular jockey Jason Waddell was suspended and unsuccessfully sought a stay of proceedings.

Saturday's victory gave Bosson his fourth Oaks win after She's Country (2000), Bramble Rose (2003) and Princess Coup (2007).

Keep The Peace started third favourite today at $6.40 behind Zarzuela and A Chance To Dream.

Keep the Peace is now unbeaten in three starts at Trentham and took her career record to four wins from eight starts.

She was runner-up in the One Thousand Guineas at Riccarton in November.