MELBOURNE: Australia's bowlers had to work hard for their wickets but completed an emphatic 177-run victory before the close of day four of the second test against West Indies on Tuesday, taking an unassailable 2-0 lead in the series. Wicketkeeper Denesh Ramdin and captain Jason Holder built a brave 100-run stand after tea to slow Australia's march at the Melbourne Cricket Ground, but all-rounder Mitchell Marsh broke the partnership with some fiery pace bowling and took 4-61 to complete the triumph. Chasing an imposing 460-run target for victory, the West Indies batsmen battled hard in sublime conditions but were bowled out for 282 in the penultimate over of the day. Having beaten New Zealand 2-0 at the start of the home summer, Australia captain Steve Smith celebrated his second series win in charge following the retirement of Michael Clarke. He was disappointed, however, that his bowlers let three wickets go begging by over-stepping the crease, adding needless burden to the task of securing victory on an unresponsive pitch. 'We probably let ourselves down a little bit, obviously with the no-balls,' he told reporters. 'I don't think we dropped our level, it was a tough wicket to take wickets on. You really had to grind it out and work extremely hard. 'We got the job done.' West Indies captain Jason Holder, who top-scored for his side with a defiant 68, said the loss 'hurt' but he was comforted by his team's improvement from Hobart, where they were thrashed by an innings and 212 runs and roundly condemned for a perceived lack of effort. All the West Indies' top seven batsmen made starts in the second innings but only Holder and Ramdin made it past 50. More concerning, their bowlers could take only six wickets in the match and allowed Smith's men to pile on 551 runs in the first innings. 'We probably showed a lot more belief when we went into bat,' Holder told reporters. 'Obviously our bowlers still need to be a lot more disciplined.' Smith declared Australia's second innings closed at 179-3 before the start of play on day four but it was slow going, with only opener Kraigg Brathwaite falling for 31 in the first session. By tea, three more wickets had tumbled and victory was in sight for the Australians. Spinner Nathan Lyon, named man-of-the-match after taking seven wickets, dismissed West Indies' last specialist batsman in Jermaine Blackwood for 20 shortly after the break and Marsh had Ramdin caught behind for 59. Lyon returned to bowl Carlos Brathwaite for two, knocking off a single bail, leaving the last three batsmen to deal with the new ball. Although Holder soaked up another half-hour with fellow paceman Kemar Roach, he spooned a catch off Marsh straight to mid-on in the day's 87th over and it ended quickly from there. After dismissing Roach, paceman James Pattinson ran in from long leg to complete a fine catch after Jerome Taylor slogged Marsh high into the sky, and the Australians celebrated finishing their work a day early.