Having suffered the shock of losing his captain Andrew Strauss in the first over, Cook compiled a superbly-controlled 114 not out to put England in control against a South African attack that lacked energy and spark – their limited preparation being the obvious bearer of the guilt for that.
It had all started so well for the tourists when Strauss, having initially been reprieved by umpire Steve Davis, was condemned by the review which showed Morne Morkel had trapped him lbw for a duck with the fourth ball of the day.
But South Africa’s response to the breakthrough was lax – Dale Steyn was only introduced in the 11th over and there was a glaring lack of interrogating, hostile fast bowling.
Cook and Jonathan Trott steadied and then rebuilt the innings, taking England to 70 for one at lunch. They batted through the second session, Cook reaching his fifty first in 137 minutes and 98 balls, with Trott following an hour later off 190 minutes and 127 balls.
Trott was impressive as he played the ball late and worked anything back-of-a-length through the leg side to good effect.
He eventually fell in the fifth over after tea as he was drawn into a drive at Morkel, who had found the perfect length and gained a bit of away movement to find the edge, presenting wicketkeeper AB de Villiers with an easy catch. Trott had made the South Africans work hard for his wicket, scoring 71 off 162 balls and he stroked nine boundaries.
Cook had shared in a key second-wicket stand of 170 off 348 balls with Trott, and he would bat on through to stumps, collecting 11 fours and a six off his 283 deliveries.
Kevin Pietersen replaced Trott at the wicket and kept the momentum going England’s way as he breezed to 42 off 72 balls. But his team would have loved the controversial former South African to bat through to the close; instead he got himself out in the over before the second new ball was due.
There was very little pace and bounce in the sluggish pitch for the fast bowlers, but the admirable Jacques Kallis really bent his back and dug in the 79-over-old ball, Pietersen went for the hook and will be filthy with himself for just lamely gloving a catch to De Villiers.
Ian Bell (10*) survived nine overs of the second new-ball with Cook and South Africa will be desperate to remove the in-form ginger and the brilliant left-hander early on the second morning.
Cook, compact and simple in his approach, left the ball brilliantly and punished anything loose with aplomb.
Morkel was the most successful of the South African bowlers with 2-44 in 18 overs, but the performances of the underdone Steyn and the loose Imran Tahir were disappointing.