John Hyndman was knifed in the neck before being dumped in a stairwell and left to die in Ruchazie, Glasgow, last July.
John Kenna, 49, and Archie Paterson, 53, were convicted of the murder following a trial at the High Court in Glasgow.
Kenna and Paterson showed little emotion as they were taken to the cells amid an increased police presence in the court.
Prosecutor Paul Kearney said Mr Hyndman, 48, of the city's Haghill, was the victim of a "spontaneous and concerted attack" by the pair.
He was struck with such force that the blade cut into his spine.
His body was dragged out onto the landing, before Paterson was seen throwing buckets of water to try and clean the blood-soaked property in Blairlogie Street.
Judge Rita Rae QC jailed both Kenna and Paterson for life, imposing a punishment part of 18 years. She added a further two years after they were also convicted of attempting to defeat the ends of justice.
Judge Rae told them: "The description of brutal is one I agree with, but it is also senseless. Not satisfied at killing him, you unceremoniously dragged him from the flat and abandoned him in the landing."