Shane Watson's 176 is his third Test century, and easily the highest - his previous-best was 126 against India in Mohali in 2010. Since that Test match and before today, Watson had gone past 50 ten times in 46 innings, without once going on to a century: his highest during this period had been 95.
The century by Watson was the first by an Australian No.3 batsman in nearly two years: the previous hundred was Shaun Marsh's 141 against Sri Lanka at Pallekele in September 2011. In 48 innings since then and before this match, Australia's No.3 batsmen had averaged 23.17, with a highest of 87. They were the only team whose No.3 hadn't scored a hundred during this period.
The last time an Australian No.3 batsman scored 150 or more in an overseas Test was at Cardiff in 2009, when Ricky Ponting made 150. In all there have been 20 instances of Australian No.3s scoring 150 or more overseas, of which Ponting and Don Bradman have contributed five each. Among those 20 instances is Jason Gillespie's unbeaten 201 against Bangladesh in Chittagong in 2006.
In just this one innings, Watson scored 34% of the total runs he had scored in 17 previous Test innings in England: in those 17 tries, Watson had managed 520 runs at an average of 30.58, with a highest of 68.
The on-side was clearly Watson's preferred scoring area in this innings: 115 of his 176 runs came in that region, and 91 of those in the arc between midwicket and the sightscreen. Fifteen of his 25 fours came on the on-side. The bowler who suffered the most at his hands was debutant left-arm spinner Simon Kerrigan, who leaked 35 runs off 25 balls to Watson, and overall went for 53 in eight overs.
Stuart Broad has been Michael Clarke's nemesis in this series, but this time Clarke fell to James Anderson, another bowler who has had plenty of success against him in the past. Anderson dismissed Clarke for the eighth time, sneaking past Broad, Ishant Sharma and Dale Steyn, who have each dismissed him seven times. Broad still has the slightly better average against Clarke, though: his seven dismissals have cost him 163 runs (average 23.28). Anderson averages 27.50 runs per dismissal against Clarke.
The 145-run stand between Watson and Steven Smith is the sixth century stand for Australia in this series, and the third-highest. Watson also added 107 for the second wicket with Chris Rogers, which makes this the first instance of two century stands in the same innings for Australia in this series. England have also had six century partnerships in this series.