Danny Cipriani is convinced Wasps will start their Heineken Cup challenge with a bang - after taking a rocket from coach Shaun Edwards.

Wasps head into European action against Castres this Sunday having suffered five defeats from six games in a disappointing start to the new season. The usually water-tight Wasps defence has leaked an average of 24 points per match and Edwards pulled no punches in his assessment of their performances so far.

It is not the easiest of environments for Cipriani to slot back into as he continues his comeback from a gruesome ankle injury. But the 20-year-old England fly-half is ready to play a full 80 minutes against Castres - and he is determined to stop the rot.

"It will be a massive game. Castres are one of the best teams in France and as a team we have got to come together and move on," Cipriani told PA Sport. "Once we click then the old Wasps will come back. This weekend we are going to see a different side because I can feel things coming together.

"We will be more aggressive, we will run harder and we will have that edge that we lacked. It is about time we stand up and make our fans proud. Shaun Edwards has hit home with a few truths and really made a few points clear to some of the guys. We needed it and it needed to be said. He will make sure that when we take the field on Sunday it will be the Wasps of old."

On the surface it is difficult to see where Cipriani's confidence is founded, given the recent run of results and the difficulties Wasps have had in adapting to the new laws and refereeing directives. But he believes the narrow league and cup defeats to Bath (27-23) and Gloucester (24-19) respectively over the last week prove Wasps are not far off.

"Last Wednesday, Bath played some of their best rugby all season and we played quite poorly - but we were only four points away from them at the end of the match," said Cipriani. "That shows that if we click, as we can do, then it will be a different team and we can put a lot of points past sides."

Wasps failed to reach the knock-out stages of the Heineken Cup last season after finishing third in a nightmare group behind eventual champions Munster andClermont Auvergne. The system was changed this year and Wasps benefited from being seeded, but still drew Castres, Leinster and Andy Robinson's Edinburgh.

"Last year we had a very tough group. This year it is not much easier at all," said Cipriani. "Wasps want to win every game and every competition we take part in. We have got a side that can really challenge for it and I think you will see a different Wasps this weekend."

Cipriani played 50 minutes and scored 11 points against Bath last Wednesday night in his first game back since suffering a fractured dislocation of the ankle. The Wasps medical staff are anxious not to rush things, so he sat out the Gloucester match at the weekend.

"He is fit, there's no problem," said Wasps director of rugby Ian McGeechan. We just decided we wanted his recovery to be a bit longer than three days."

But with a full week of preparation under his belt, Cipriani will be ready to put in a full shift against Castres.

"The ankle feel really good. I enjoyed it last Wednesday and now I am looking forward to playing Castres," he said. "I am hoping to play 70-80 minutes at the weekend. I feel ready, I feel like I can play a much bigger part than I did last week.''

Cipriani spent the afternoon with a group of Under-13 players from Trinidad and Tobago, who have flown in to take part in the Tullow Oil touraid Cup. Cipriani is an ambassador for the charity, which aims to give children from underprivileged backgrounds the chance to experience new cultures.

It was a special occasion given his father, Jay, hails from Trinidad and Tobago and Cipriani said: "It is lovely being here. It makes me think of my cousins back home. Hopefully these kids will have a great experience, make friends for life and enjoy learning about the new culture."

The touraid Cup will be played on Thursday and Saturday this week and includes teams from Tanzania, Pakistan, Uganda, Namibia, Ivory Coast, Madagascar, Ghana, South Africa and India. Each team will comprise players from both the touring team and their host school.