Watson puts Australia in charge
Shane Watson's first Ashes century put Australia in the driving seat on the first afternoon of the fifth Investec Ashes Test as England debutants Chris Woakes and Simon Kerrigan suffered stage fright.
With the series already won, England made the surprising decision to blood all-rounder Woakes and slow left-armer Kerrigan in a revamped five-man attack, but it was Watson who stepped into the limelight after a troubled summer.
Batting for the first time this series at number three, Watson reached tea on 121 not out, the central plank of Australia's 183 for three.
It was just his third Test hundred and first in almost three years.
His innings gained impetus when he bullied Woakes and Kerrigan in the morning session, with the pair bowling a combined seven overs for 58.
James Anderson fared better, taking two scalps to move clear of Bob Willis as England's second highest wicket-taker with 326.
England's team sheet had been a surprise, with Jonny Bairstow's omission alongside the injured Tim Bresnan leaving just five specialist batsmen.
Kerrigan's inclusion, meanwhile, meant England employed two frontline spinners on home turf for the first time since the opening Ashes Test of 2009.
That meant disappointment for Chris Tremlett, who had been expected to make a first appearance in 18 months on his home ground, and fellow paceman Steven Finn.
After an hour the game was evenly poised at 37 for one, England perhaps marginally happier having dismissed David Warner for six.
Anderson was the bowler, pushing one across the left-hander and picking up the edge to gift Matt Prior a regulation catch.
That brought Anderson level with Willis and he must have fancied an early sight of Watson, whose tendency to fall lbw has been a feature of the series.
Anderson rapped him on the pads when he had just eight to his name, but umpire Aleem Dar favoured the batsman in a tight call.
At the other end, Stuart Broad had been unlucky not to join Anderson among the wickets.
He beat Chris Rogers with his fifth and sixth balls of the morning, one an edge that fell just short of slip and the next a strong lbw appeal.
The game changed swiftly after the drinks break, with Watson's natural aggression easily trumping the inexperience of England's newcomers.
Woakes managed one maiden in his opening burst, but otherwise served up too many loose balls and his other four overs cost 30, mainly to Watson.
He also lifted Graeme Swann for a mighty straight six, perhaps a sign that the time was not ripe to introduce Kerrigan.
But Cook tossed the 24-year-old the ball moments later and the result was dispiriting.
Watson instantly went on the attack, flaying Kerrigan for six boundaries in two overs that cost a total of 28.
It was poor from the slow left-armer, who offered up one full toss and a handful of inviting long hops.
A pre-lunch century briefly looked possible until Broad returned to restore some control.
At the interval Watson had 80 of Australia's 112 for one, with Rogers sedate on 21.
The latter added two more in the afternoon before his nemesis, Swann, sent him back via a smart slip catch by Jonathan Trott.
Broad delivered a fierce spell of short bowling from the Vauxhall End, almost bowling captain Michael Clarke off his arm guard and then striking Watson a nasty blow between neck and jaw.
The Australian spent several minutes regaining his composure but was fit to continue on 91.
Clarke never looked content at the crease and had scraped together seven runs when Anderson brought one back in to him, uprooting off stump having flicked the front pad.
Watson did not allow that to distract him and reached three figures with a clip for three.
His elation would have been short lived had Cook held a simple catch off Anderson with the opener on 104, but the skipper grassed it.
Kerrigan was given one over before tea, but a looping beamer at Smith suggested the nerves had yet to dissipate.