Wendy Alexander has been handed a return to Labour's front bench team by party leader Jack McConnell.
Ms Alexander has been tipped as a future Labour leader
Ms Alexander, 44, has been given the key role of shadowing the SNP's John Swinney in his job as secretary for finance and sustainable growth.
The former enterprise minister is seen as a future contender for the Labour leadership if Mr McConnell stands down.
Iain Gray has received the brief for enterprise, energy and tourism after his return to Holyrood.
Mr Gray replaced Ms Alexander as enterprise minister following her shock resignation in 2002, but lost his seat to Conservative David McLetchie a year later. He won the East Lothian seat on 3 May.
Mr McConnell's reshuffle has seen former parliamentary minister Margaret Curran given the job of justice spokeswoman.
Mrs Curran has swapped places with former justice minister Cathy Jamieson, who is the spokeswoman for parliamentary business.
Hugh Henry has retained the party's education brief and Andy Kerr remains at health, while Rhona Brankin has been appointed as the party's spokeswoman for rural affairs and the environment.
There were promotions for Pauline McNeil, Ken MacIntosh and Paul Martin, while former finance minister Tom McCabe was named as the party's nomination for the Scottish Parliamentary Corporate Body.
There has been speculation that Mr McConnell might step down as Labour leader, but after naming his new team he pledged to form an "effective opposition" to the new SNP executive.
Iain Gray has been re-elected to Holyrood after losing in 2003
Mr McConnell said: "While we disagree strongly with Alex Salmond's decision to create a guddle of cabinet responsibilities, Labour will form an effective opposition by shadowing each minister directly.
"I am particularly pleased to welcome Wendy Alexander and Iain Gray back to frontline politics, and to promote Pauline McNeill, Ken MacIntosh and Paul Martin who will use their parliamentary skills to very good effect in holding the new government accountable.
"My new front bench team are able, experienced and committed to building a better Scotland."
The former first minister said his team would meet every week.
He added: "We will oppose Nationalist plans which would damage Scotland, but we will also seek to work with the new government, and others, where we can agree measures which will build up Scotland."