David Moyes (Real Sociedad)
The former Everton boss is rebuilding his career in Spain after a demoralising spell at the helm of Manchester United. While Sociedad sit in the top-half of the La Liga table, they are some way adrift of European football next season.
Napoli will be much more likely to be competing in the Europa League next year, and if Benitez leaves, then they may turn to Moyes.
Slaven Bilic (Besiktas)
The former defender was one of the most sought-after managers a few years ago, after his work with the Croatian national side. But he decided to continue his development in Eastern Europe, where he remains with Turkish side Besiktas.
It still seems only a matter of time before he gets a higher profile job, and former club West Ham may appeal to the 46-year-old.