England cannot settle for "small incremental changes to make the difference" to their men's cricket setup if they want to compete, according to interim manager director Andrew Strauss.
Strauss left his role at the top of English cricket in 2018 but returned in a temporary role following the 4-0 Ashes thrashing in Australia.
The first of former England captain Strauss' changes saw head coach Chris Silverwood dismissed, with Paul Collingwood stepping up in the interim for the tour of the West Indies.
Joe Root's much-changed tourists, without star bowlers James Anderson and Stuart Broad, shared the spoils in an uneventful first Test with Kraigg Brathwaite's West Indies side in Antigua, but Strauss is aware that success will not arrive "overnight" for a struggling England side.
"The results do not lie," former opener Strauss, whose managing director role started to be advertised for a long-term successor on Monday, told the BBC.
"We have been number one in the world in Test cricket for 12 months in the last 42 years. Small incremental change isn't going to make the difference we need.
"We need to be bold and ambitious."
Strauss headed the England and Wales Cricket Board (ECB) committee that called for a full independent review into English cricket's domestic setup, and he appreciates that "time is ticking" to find a solution in appointing a managing director, who will find the next head coach of the men's team.
"There is a slight ticking clock in terms of the start of the international summer at the beginning of June and we want to get that person in position," he continued.
"It will be their decision around the coach and/or coaches as well, which hopefully will also be in position by the start of the summer, but there is a bit of time pressure for us to make that happen.
"It's going to be his [the new managing director's] team and so he has to look at how he wants to structure the England high-performance department.
"Whether he goes down the single coach or two coach model, he has to have the people that he feels can work with him and has a similar philosophy."
South African Gary Kirsten has been floated as Silverwood's red-ball successor, but Strauss believes whoever the next managing director and head coach are, England have to compete in all formats.
Questioned on who the new managing director may be, and whether they would have to be English, Strauss responded: "I've always been uneasy in saying overseas candidates cannot do the role.
"But what a time to get involved. It is very rare you get the opportunity to start with a blank piece of paper and this person is going to have that.
"Despite the doom and gloom around English cricket, there are a lot of good players out there. We are not going to become brilliant overnight but I think we have a lot of the raw ingredients in place.
"While a lot of the focus post-Ashes has been on red-ball cricket and the domestic structure, our project is broader than that.
"Our ambition has to be for us to be the best team in all formats. We have the ability to do that, and in order for that to happen, we have to look at the whole system.
"We have to accept we have never had a system that has produced that.
"Whatever your focus on red-ball cricket, it's like a Rubik's Cube and it affects white-ball cricket. You cannot look at them in isolation, you have to look at them together.
"The game around us has been moving very quickly. Not just our international players, but our domestic players are playing a lot of cricket abroad in the winter and it's time to ask what our role is in all of this.
"How do we protect our own system but also enhance that system?"