Kolkata, Nov 12 India pacer Mohammed Shami on Monday said the possible absence of Steve Smith and David Warner would weaken the Australian side, but India would still require a sound plan to achieve success Down Under.Banned Australian captain Smith and vice-captain Warner could well make an early comeback in the India series after Cricket Australia announced that it will give "due consideration" to the Australian Cricketers Association's (ACA) demand for revoking the ball-tampering bans on the premiere cricketers."If those two don't play, they will obviously be weakened. But in the end, you have to stick to your plan and work on your strengths," Shami told reporters on the sidelines of Bengal vs Madhya Pradesh Group B Elite Ranji Trophy match.ACA has increased the pressure on CA to lift the ban on Smith and Warner ever since an independent review claimed that the 'culture' nurtured by the board contributed to the ball-tampering scandal, which rocked the nation in March.Asked about the team's preparation ahead of the Australia tour, Shami said the pace battery would look to work on their line and length."As a fast bowling unit, we did well in England. We are preparing for the Australia series and watching a lot of videos. The plan is to focus on the series as much as possible as the opponents are very strong. We will work on getting the line and lenghths right," Shami said."We will always try to do our best. Winning or losing also depends on luck. We will give our 100%."The four-Test series begins on December 6 at the Adelaide Oval.In England, Shami did not fare all too well despite bowling well. The 28-year old took 16 wickets in five matches.In white-ball cricket, the Bengal fast bowler got a chance to prove his mettle against the West Indies in the first two One dayers where first choice quicks Jasprit Bumrah and Bhuvneshwar Kumar were rested.Shami had two average games leaking runs aplenty on each occasion and was subsequently dropped for the last three ODIs.Asked about his chances in the World Cup next year with India having a lot of pace options now, the latest being Khaleel Ahmed, Shami said he can only focus on improving his performance."It depends on who is fit and who is not during that time. My performance will be evaluated and I will expect to get a chance if I do well. If I don't, I have to accept that too."I will always look to better my performance and not worry about selection."