The Brazilian has been offered to Celtic in a pounds 4m move by his Spanish club Deportivo La Coruna, just at the same time as Jorge Cadete heads off in an Iberian direction with a move to Real Sociedad almost completed.
However, Larsson and Jackson two of the half-dozen new faces brought in by the head coach, Wim Jansen, combined with stunning effect to dispel not only the clouds gathering around Celtic but also the doubts as to whether the Celtic coach really needs another striker.
Even this early in the season, this was a meeting of top against bottom. The surprise though was that newly promoted St Johnstone occupied the former and Celtic the latter.
However, current form was indeed underlined when George O'Boyle almost gave Saints the lead after just 11 minutes. Callum Davidson cut in from the wing and struck a fierce shot which the Celtic goalkeeper, Jonathan Gould, unwisely opted to parry. O'Boyle put the ball into the net but he was ruled offside.
Celtic were stung sufficiently and Larsson twice within the space of four minutes thought he had found a way through. Gould then produced an astonishing save in the 35th minute saving at point blank range a fierce shot from O'Boyle. The value of that moment became evident when Celtic went ahead in the 44th minute.
Larsson started the move in the centre circle, raking a pass out wide to Simon Donnelly before sprinting 40 yards to finish off the cross with a bullet of a header past Alan Main.
Jackson sealed the victory in the 64th minute, forcing an error from defender Stuart McCluskey before crashing a shot past Main from 20 yards.Reuse content