3:10 AM GMTAlex MalcolmFacebookTwitterFacebook MessengerPinterestEmailprintInterim coach Rumesh Ratnayake believes Sri Lanka must have better preparation on fast pitches prior to next year’s T20 World Cup in Australia if they are to be competitive in the tournament.Sri Lanka were beaten out of sight by Australia in the three-match T20I series that concluded on Friday after coming to Australia with high hopes following a series whitewash of the world No.1 team Pakistan last month.The visitors were badly exposed by Australia’s bowlers, scoring just 99, 117 and 142 in the three games, with Kusal Perera the only player to make a half-century. They also struggled to contain the Australian top order who thrived in home conditions with David Warner scoring 217 runs without being dismissed.Ratnayake suggested Sri Lanka’s build-up was inadequate and they need to prepare better for the World Cup next year.”I thought we gave a good fight,” Ratnayake said after the Melbourne loss. “We learned a lot of lessons from this. Our preparation wasn’t the greatest. I don’t say that as an excuse, but these are lessons that we can learn if we are coming again for a T20 series or any time soon to Australia on a tour. We have…