Simone Inzaghi’s side already had little hope of recapturing the league title conceded to local rivals AC Milan last season and the yawning gap between them and Napoli widened following an underwhelming display.
Napoli cruised past Cremonese 3-0 on Sunday and look with each passing week more likely to claim a first league crown since 1990.
Second-placed Inter are three points ahead of Atalanta, Roma and Milan in the race for next season’s Champions League.
Lazio are five points back in sixth after being beaten by Atalanta in Rome on Saturday night.
Monday’s draw is a good result for troubled Samp but a point does little for the survival hopes of a team firmly ensconced in the relegation zone.
Dejan Stankovic’s side have collected 11 points from their 22 matches and are eight behind Spezia, who sit just outside the drop zone and drew at Empoli on Saturday.
