Iron ore accounts for about 80% of Rio’s earnings and the business undoubtedly got Rio through the global financial crisis.

Melbourne-born Walsh joined Rio in 1991 after a 20-year career in the automotive industry.

He was appointed CEO of Rio’s aluminium business in 2001, a role he held until 2004, when he was made CEO of the iron ore division.

Over the past seven to eight years, he’s presided over a rapid expansion in the Pilbara.

In June 2009, Walsh was appointed as an executive director to the board of Rio, and in November 2009 he was named CEO of Rio Tinto Australia.

Perth-based Walsh will relocate to London to take on the role and be paid about $A7.8 million per annum in salary and incentives.

"We are fortunate to have such a capable and highly experienced executive as Sam to take over and to ensure there will be a rapid and seamless transition,” Rio chairman Jan du Plessis said.

“He is ideally placed to cast a fresh eye over how we address the challenges and opportunities in the business, and derive greater value from it.”

IG Markets said Walsh’s results spoke for themselves.

“He has continued to hit record production levels and kept Rio’s iron ore revenue ticking over under tricky trading conditions,” it said in a morning note.

“He will also bring a much stricter and disciplined approach to further investment and capital management.”

However, Macquarie believes Walsh’s ascension to the top job was merely a case of “right place, right time”

“While Walsh’s track record speaks for itself and his established cost focus will be well received in the current environment, it nevertheless feels like he was merely the last man standing and will be taking something of a caretaker role until a more permanent solution can be found,” Macquarie said today.

“What’s more, we note that within a year Rio will have a new CEO, CFO and heads of both Iron Ore and Strategy (along with all the associated reshuffling).”

Walsh has a Bachelor of Commerce from Melbourne University and has completed a Fellowship program at Kettering University, Michigan.

He is a fellow of the Australian Institute of Management, the Australasian Institute of Mining and Metallurgy, the Australian Institute of Company Directors and the Chartered Institute of Purchasing and Supply.

He is also a director of Seven West Media, a vice-president of the Australia-Japan Business Cooperation Committee, chair of the BG Australia Advisory Board, president of Scouts Australia (WA branch) and patron of the State Library of Western Australia Foundation and of the University of Western Australia's Hackett Foundation.

In 2007, Walsh was named WA Citizen of the Year – Industry & Commerce and an Australian export here and in 2010, Walsh was made an officer in the general division of the Order of Australia and awarded an Honorary Doctor of Commerce by Edith Cowan University.

The WA arts community will miss him with art-lover Walsh taking a very keen interest in the scene, with Rio heavily involved as a sponsor as a result.

Walsh chairs the Black Swan State Theatre Company, the WA Chapter of the Australia Business Arts Foundation and the Chamber of Arts and Culture WA.

In 2011, Walsh was awarded the Australia Business Arts Foundation's Richard Pratt Business Arts Leadership Award and last year he was awarded the Gold Medal by the AICD for his leadership contribution within the wider community.

While an announcement is yet to be made, Pilbara president Greg Lilleyman is Walsh's likely successor in Perth, having stepped up his public profile over the past year.

This article first appeared in ILN's sister publication MiningNews.net.