James Anderson says England must polish off Australia's lower order and then produce a strong second innings batting performance on day four in Cardiff.
Day three of the first Ashes Test finished with Australia 44 runs ahead on 479-5.
"It was tough for us but at least I managed to get a couple of wickets," said Lancashire paceman Anderson.
"We haven't bowled consistently well enough in this game and we need to be quite aggressive in the morning."
The weather could have quite a say in the match on Saturday, with rain forecast.
On Friday, England took no wickets between lunch and tea as Michael Clarke and Marcus North virtually batted the home side out of contention.
But Clarke was among those to describe the pitch as a good one for batsmen.
"The wicket's nice and very good to bat on," said the Australian, who fell late in the day for 83, becoming the first dismissal under floodlights in Test cricket in Britain.
TOM FORDYCE BLOG"Hopefully the rain can stay away on Saturday and we can go on and get a good lead. If we can get a bit of sunshine, with no rain, then come day five the wicket might really turn for us.
"Hopefully we can make England bat last on that wicket."
Anderson said he felt an improvement in his own performance.
"I bowled a lot better this morning. On Thursday I didn't hit my straps and didn't have much rhythm. But all credit to them, they played very well in the middle session and made it very difficult for us to bowl at them.
"But we know what to do in the morning. It's still a good pitch, the guys have all got in in the first innings, the pace is quite slow and hopefully we can put a big score on."
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