New London Welsh defence coach Rowland Phillips says he is determined to help turn around the fortunes of the Premiership's bottom side.
Welsh have conceded 399 points in nine game across three competitions and are yet to win a game this term.
Phillips left his post at Neath to move to the Kassam Stadium on Monday.
"I'm not here to turn a 50-point defeat into a 30-point defeat," Phillips told BBC Radio Oxford. "I'm here to make defence really important."
Phillips, formerly defence coach for Wales, added: "We've got to build our game around defence and once you get that culture then you can win games through defence. That's where we are.
"I'll by trying hard to change the culture as we have to have the mentality that defence wins games. If we are smart we can change things quickly."
The 49-year-old was part of Gareth Jenkins' coaching team for the 2007 World Cup and also worked in that role at Ospreys, Ebbw Vale and Aironi Rugby in the Pro 12.
He admitted it was a wrench to leave Neath, but the opportunity to coach in the Premiership was too good to turn down.
"This is a full-time professional opportunity, at Neath it's semi-professional and you only get to see the players two nights a week," he said.
"On a professional level this was an opportunity I could not turn down, but from a personal point of view it was difficult because my family is there, it's a club I have a strong association with and they are going through a tough period."
Phillips, who made 290 appearances for Neath, spent two seasons with London Welsh as a player, making 66 appearances and scoring 18 tries.
And he is well aware of the challenge awaiting him at the Oxford-based club.
"This is as close as you can get to international rugby, with the quality of the players and the general intensity of the competition and the professionalism of the athletes," he added.
"This steps it up to the high end of the game. That makes it exciting for me, I'm really looking forward to this challenge.
"Having looked at the last few games what I see is a big enthusiasm from the players. They really want to push up hard from defence, sometimes it's about less effort and being smarter.
"Space is such a valued commodity in this competition but you can't sacrifice your own structure."