Peter Siddle started his day the way he had started this tour. Short on rhythm, variable in line and fickle in length, he landed at least two balls an over in places the batsmen would welcome, as Jonathan Trott and Joe Root helped themselves. Essentially, Siddle was re-enacting several of the displays he had offered for Australia A and then the touring party proper: a bowler in search of his best, but seemingly unsure of where to find it.
After four overs and 27 runs, Michael Clarke withdrew Siddle from the attack. At that moment many who had questioned Siddle's place in the team, despite his sustained displays of quality over the past 20 months, assumed a state of some justification. Was this another case of the Jason Gillespies? Clarke, and Australia, could not possibly afford it to be so.
Briefly, Siddle pondered his future at fine leg, no doubt heckled by some of the throatier members of an ample Nottingham crowd. But after two overs, Clarke summoned his most senior bowler again, switched around to the Radcliffe Road End. He had not been taken off, merely changed ends.
The break, and the change, gave Siddle a moment to think, and perhaps to focus. What did the circumstances require? Nothing short, nothing wide, nothing arrowing into the pads. Something that would swing, but also force Root to play. Something that would surprise him, and ideally dismiss him. Something to rouse Siddle from his early series slumber. Eureka! A yorker.
What Siddle sent down was to be the best encapsulation possible of how he has progressed since late 2011, when he was dropped from the team in Sri Lanka before redefining his capabilities with the help of Craig McDermott. Full, accurate, fast and swinging away just enough, it was through Root before England's latest opener had time to get his bat down. Even when he did, it was on a line not taking the swing into account. The bails were scattered, and Siddle exultant.
On the Australia balcony, the coach Darren Lehmann could feel somewhat satisfied too. He had challenged Siddle in the lead-up, arguing that no bowler could be allowed to mail in tour match displays and then assume everything would be fine when the big day arrived. Siddle had responded by upping his speed and direction considerably in the nets at Trent Bridge, enough for Brad Haddin to speak glowingly of his form. Lehmann described Siddle's effort in terms of leadership after his younger proteges James Pattinson and Mitchell Starc had sprayed the new ball.
"I think we needed that experienced head in the end, didn't we?" Lehmann said. "It's the first day of an Ashes series and it's pretty big, so for the younger guys they probably got overexcited with the new ball more than anything else and they understand that. But Peter stood up when it counted and did really well - five-for on the first day and led the attack as we expect him to do and got some really crucial wickets.
"He just bowled exactly as he wanted to and did it for us, apart from the first spell where he went around the park a little bit, but after that he locked in and was very good. We've got some high-class quicks in our squad, we've got five of them, so we've got to pick what is the best pace attack at each venue to get 20 wickets. So far we've got 10, we've got to get another 10 in this one and then we move to Lord's, so we can't look too far ahead but he was outstanding today and that's what we wanted from him."
Root's dismissal was to be followed up grandly, each successive batsman defeated by a ball that tempted and ultimately confounded. Kevin Pietersen's jumpy technique was exploited by a ball he was compelled to chase. Trott's patience was tested and ultimately broken by a full ball angled in from wide of the crease. Ian Bell was out to a ball almost the equal of Root's; angled in then curling nicely away. And Matt Prior's predilection for thrashing through the off side was artfully exploited with a shortish square cover and a fine overhead catch by Phillip Hughes.
These incisions reduced England from 78 for 1 to 180 for 6, and
opened up a door that Pattinson and Starc would charge through to round up the innings for a mere 215. Siddle's performance was not his first barnstormer on the first day of an Ashes series - his hat-trick and 6 for 54 at the Gabba will remain indelible. But as a tone setter for the bowlers it was invaluable, providing his younger but more gifted counterparts a template by which to harry England for the rest of the series.
Australia's batting would then find familiar struggles under cloud that refused to shift and against bowling of similarly high quality. But as with England at Lord's in 2005, the less fancied team had demonstrated the vulnerability of the favourites, and that was largely due to Siddle. He will now hope that this Ashes tour will follow the pattern of his day, and his tour so far - an indifferent start, but a hell of a finish.
Daniel Brettig is an assistant editor at ESPNcricinfo. He tweets here