However, Sarri pointed out that such a cull would stifle the growth of the sport and a better solution would be to streamline the international fixture programme.
"An 18-team league has the pro of reducing the number of games and the con of taking away a dream from many cities, reducing the number of potential football fans in the long term," Sarri said on the eve of the match in which both Napoli and Feyenoord will be looking for their first group phase victory this season.
"I think we should blame the national team (for the crammed calendar as we should) find a specific window during the year when the national teams play... and the rest of the season some time should be given to clubs because this would give more quality to the games."
Sarri's views are in contrast to Napoli president Aurelio De Laurentiis, who said on Friday that a 16-team Serie A with just one relegation spot would make the league more competitive.
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In 1988 Serie A expanded to 18 teams before increasing to the current 20 in 2004.
Tavecchio said on Monday that he hopes to find a "reasonable solution" to cut the number of teams in Italy's professional leagues in three to four years.
Tavecchio told Italian radio channel Rai Gr Parlamento that he will start discussion at the beginning of 2018 with the leagues and the professionals involved.
He suggested last month as well that it could be possible to achieve a reduction of two teams in each of Italy's professional leagues within three years.
(Reporting by Silvia Recchimuzzi in Gdynia, editing by Pritha Sarkar)
