West Ham must look to add a central defender in January and a Moyes reunion could be the perfect addition.
The east Londoners have conceded a huge 26 goals in 13 league games this season, and that average of conceding two goals a game must dramatically decrease if the Hammers are to stay afloat under Moyes.
Jose Fonte and James Collins are both way into their thirties, while Winston Reid and Angelo Ogbonna turn 30 next summer, with all four suffering plenty of injuries throughout the calendar year.
Portugal international Fonte is sidelined until the new year, and Collins is out of contract in June which could see the Hammers offload him in the January transfer window to avoid losing him on a free.
That highlights just how much Moyes needs to sign a centre-back at the London Stadium, and he needs someone he can trust - someone he can place his faith in to stem the flow and remove some of the pressure on Joe Hart.
The Sun claims Manchester City are interested in Real Sociedad centre-back Inigo Martinez, 26, after scouting the Spaniard throughout the 2017-18 campaign. But Moyes could have the upper hand, after working with the defender during his time at Sociedad.
A four-time Spain international, Martinez is worth £18million according to TransferMarkt and has been quoted by Sky Sports as saying that he is a fan of Moyes' aggression and intensity in training sessions.
"Above all it is the intensity he brings to training, in the aggression he demands," Martinez said in 2014. "He is really on top of everything, he pressures you constantly from the side of the pitch and this is something that motivates players."
That could throw Moyes into pole position to sign Martinez ahead of City, as the Hammers would also be able to guarantee Sociedad's star defender first-team football - while a move to City would see him compete with the likes of John Stones, Nicolas Otamendi and Vincent Kompany.
Known for his speed at centre-back, Martinez is almost unbeatable in the air but possesses nimble footwork and an intricate array of passing; synonymous with Spanish central defenders.
Adding him to a side that already boast three Spaniards in Toni Martinez, Adrian and Pedro Obiang, Martinez would become a mainstay of the Hammers side and provide all the tools required to survive Premier League relegation.