The defender has not featured for the club in a competitive game since making his summer switch.
Jesus Gamez during his time with Atletico Madrid
The 31-year-old is one of just two of the eight new arrivals at St James' Park this summer to have not featured for the Magpies since the start of the season.
Newcastle United manager Rafael Benitez
And Benitez explained the reason why the full-back - who, the Shields Gazette reports, is not in the squad for the club's clash with Bristol City on Saturday - is yet to feature for his team.
"I want to be sure that he's fine," he told the Shields Gazette.
"I don't want to put him in a position where he goes out there and, like with the goalkeeper [Matz Sels], it will take him time to settle down in a new league, new intensity.
"I want to be sure that he's fine, that he understands what we're looking for and that the team is all settled."
Though Gamez has no experience of the English game, let alone the second tier, he has played for the likes of Malaga and Atletico Madrid during his career so will have an idea of the pressure that will come with playing for a club of Newcastle's stature.
But after the side lost both of their opening league games, Benitez may have perhaps feared that throwing the Spaniard in too quickly could be a mistake as the supporters may have become slightly more restless and less willing to give Gamez time to settle, which may have subsequently harmed the defender's chances of proving a success on Tyneside.