Australia v England, 4th Test, Melbourne, 2nd day
Trott century builds England's lead
Peter Siddle broke through early in the day when he removed Alastair Cook•Getty Images
Kevin Pietersen was in ominously confident mood before lunch on day two at Melbourne•Getty Images
The pressure on Ricky Ponting showed when he lost it with the umpires after Kevin Pietersen was given not out•Getty Images
Paul Collingwood's miserable run with the bat continued when he was out hooking for 8•Getty Images
Trott was struck a painful blow on the knee off an inside edge during his innings•Getty Images
Siddle had his second wicket when Andrew Strauss was caught at gully•Getty Images
Pietersen flicked in the air just wide of Michael Clarke •Getty Images
Pietersen gestures at his bat after a disputed review decision•Getty Images
Jonathan Trott helped to extend England's lead with a typically stubborn innings•Getty Images
Trott acknowledges applause for his hundred•Getty Images
Ricky Ponting was involved in an ugly incident where he argued with the umpires after an unsuccessful review•Getty Images
Pietersen looked in good touch during his half-century•Getty Images
Matt Prior was given out caught behind off Mitchell Johnson before it was found to be a no ball•Getty Images
After a shaky start Matt Prior played a number of sweet strokes on his way to fifty•Getty Images