Sampdoria notched up a second consecutive victory, but SPAL paid for some howlers in defence and the Manolo Gabbiadini free kick masterclass.
The Blucerchiati are breaking away from the drop zone and showed great confidence at Marassi.
Karol Linetty benefited from two awful defensive errors for a rare brace, but there were no doubts about the quality of that Gabbiadini set-piece.
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