Ken Macintosh in the running for Scottish Labour leader role
Scottish Labour MSP Ken Macintosh is expected to run for the leadership of his party when Jim Murphy quits next month, BBC Scotland understands.
He is prepared to challenge the party's deputy leader Kezia Dugdale, who is widely expected to stand.
Mr Murphy announced on Saturday that he would resign next month despite narrowly surviving a vote of no confidence.
His departure leaves the party looking for its sixth leader in eight years.
The former East Renfrewshire MP had only been the Scottish party leader since December but he announced he would quit a week after Labour's crushing general election defeat at the hands of the SNP.
Scottish Labour frontbenchers Jackie Baillie and Sarah Boyack are understood to have ruled themselves out of the leadership contest.
Health spokeswoman Jenny Marra is said to be "very unlikely" to stand.
Neil Findlay, who stood against Mr Murphy when he won the leadership just six months ago, has said he will not go for it this time.
Ms Dugdale is widely regarded as the "obvious person" to take on the job.
But Ken Macintosh, the party's social justice spokesman, who ran against Johann Lamont almost four years ago, is preparing to have another go at securing Scottish Labour's top job.
No formal announcements are expected on Tuesday, as Labour MSPs return to Holyrood for the first time since Mr Murphy announced his decision to quit.