An 11-under-par opening round has taken England&aposs Lee Westwood directly to the top of the Mercedes-Benz Championship leaderboard, leaving several Australians off the pace. Westwood has had several opportunities to win tournaments in recent weeks but found his putting was letting him down. However, having gone to his garage at home and picked out an old mallet putter, the Englishman returned to form in devastating style by picking up 10 birdies and an eagle to record a score of 61 on the par 72 course in Cologne. The low score puts Westwood four strokes ahead of his nearest challenger, Soren Hansen, who carded a very respectable seven-under 65, while Nick Dougherty (66) and Simon Dyson (66) are both a further stroke behind in a tie for third. Peter O&aposMalley was the best of the two Australians in the elite 78-player field, carding two birdies and no bogeys in his solid two-under 70. Richard Green&aposs round was a little more erratic. He turned for home at one-under but carded three bogeys and a birdie on the back nine to be 12-strokes off the lead after carding a one-over 73. Green is still two strokes ahead of New Zealand&aposs Michael Campbell, though. Throughout the year, Campbell has made a habit of starting tournament&aposs impressively, but this time around, the Kiwi struggled at the North Rhine course. He was one-under following a birdie on seven, but that was when the rot set in, with Campbell then recording three double bogeys, a bogey and two consolation birdies coming back to the clubhouse on his way to a five-over 77. First Round of the Mercedes-Benz Championship: -11 Lee Westwood 61 -7 Soren Hansen 65 -6 Nick Dougherty 66, Simon Dyson 66 -5 John Daly 67, Niclas Fasth 67, Gonzalo Fdez-Castano 67, Simon Khan 67, Richard Sterne 67 -4 Robert-Jan Derksen 68, Bradley Dredge 68, Mikko Ilonen 68, Miguel Angel Jiminez 68, Paul Lawrie 68, Andres Romero 68 also: -2 Peter O Malley (Australia) 70 +1 Richard Green (Australia) 73 +5 Michael Campbell (New Zealand) 77