In almost simultanous posts on the social network, the pair, who are ringing in the New Year in Australia, tweeted pictures of a diamond engagement ring on Wozniacki's finger alongside a picture of fireworks over Sydney Harbour Bridge.
The star couple have a combined following of more than two million people on Twitter and have frequently used the social media website to have fun with their followers. Announcing the engagement, the Northern Irish golfer and current world number six told his followers : "Happy New Year everyone! I have a feeling it's going to be a great year!! My first victory of 2014 #shesaidyes!!"
Danish tennis player Wozniacki (23) -- also in her sport's top 10 -- tweeted the same pictures and a message saying: "Rory and I started 2014 with a bang!...I said YES!!!!"
The duo started dating in the summer of 2011
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