I think it's an important point that he beat both Nadal and Murray at that 2008 Australian Open. With regard to Murray, he came into the 2008 Australian Open right after winning Doha, would follow his AO loss to Tsonga w/a win at Marseille, and would go on to win Cincinnati, make the U.S. Open finals, win Madrid, and win St. Petersburg in 2008.
So, it was multiple big wins at the 2008 AO, just like he had multiple biig wins -- over Djokovic, Murray, and Federer -- in winning the 2014 Canadian Open.