premise: Jamie Murray is a winner.
hypothesis: Jamie Murray . He is a three-time Grand Slam doubles winner and a Davis Cup champion , currently the world No. 5 doubles player , and a former doubles world No. 1 . He has won three Grand Slam titles : the mixed doubles title at the 2007 Wimbledon Championships with Jelena Janković and the men 's doubles titles at the 2016 Australian Open and 2016 US Open with Bruno Soares . In 2013 , he began a new partnership with John Peers , winning six ATP tournaments , and reaching two Grand Slam men 's doubles finals . Murray was in the Great Britain team that won the Davis Cup in 2015 , the nation 's first success in the tournament for 79 years . With his brother Andy , he won the doubles matches in Britain 's quarter-final , semi-final and final victories .