Kevin Pietersen's half-century helped England post a total of 226 runs as they lost six wickets on day one of the fourth Ashes Test in Melbourne Cricket Ground.

Australia have already sealed the five-match Test series 3-0 to regain the Ashes. Skipper Michael Clarke has said he wants his team to move in for the kill and complete a whitewash.

England were handed a blow before Christmas as spinner Graeme Swann announced his retirement from the game with immediate effect. Monty Panesar replaced Swann in their squad.

The hosts won the toss and elected to field first. England openers did not take the pitch by a storm. Alastair Cook (27) and Michael Carberry (38) managed only 48 runs on the scoreboard before the skipper edged Peter Siddle's delivery into the grateful hands of Clarke at second slip.

Carberry walked back to the pavilion after being bowled over by Shane Watson; his partnership with Joe Root yielding the same number of runs as that of the openers. Pietersen stepped in when England were 96 with the loss of two wickets, and he held the innings together with his gritty knock.

Root (24) walked back in the 43<sup>rd over after nicking Ryan Harris' delivery into the hands of Brad Haddin behind the stumps. Ian Bell (27) partnered with Pietersen to add 67 runs to the total before following Root in a similar manner.

Ben Stokes (14) and Jonny Bairstow (10) were dismissed by the second Test hero Mitchell Johnson in the final stages of the day.

Johnson and Harris grabbed two wickets each while Siddle and Watson took one each. The only disappointment on the day for Australia was the groin injury to Watson, which forced the all-rounder to leave the field.

England will begin day two with Pietersen (67) and Tim Bresnan (1) on the pitch as Cook looks to post a respectable score in the first innings. While Clarke will hope that his bowlers grab quick wickets and keep up with his promise of putting the visitors to bed.