Yes he dug in and played very well, showing great concentration. I'd like to see his finishing wagon wheel though - I think it was in his fifties they showed one, and apart from three shots, every scoring stroke was legside! He put away his offside shots, but I think Aus lost patience and bowled on his stumps a lot, which I guess you can do when you're 400+ runs in front.
He got lucky early with an LBW call that didn't get reviewed, and you could say Williamson was unlucky with his LBW, so I guess that evens out.