Despite spending heavily over the summer to back new manager Steve McClaren, the Magpies are currently entrenched in the relegation zone after 11 games.
Perhaps more worrying than their position, 18th, is the quality of performances witnessed in the North East, with Newcastle having already conceded 22 goals – two more than rock-bottom Aston Villa.
And reports claim that the club are eager to address this with moves for Ligue 1 pair Umtiti and Sidibe.
The former shone for Lyon last term as they narrowly missed out on the French title and has since featured in Champions League action for the club.
Umtiti can play at both centre-back and left-back and has been lauded for his pace and power.
The 21-year-old is understood to have been watched by the club in recent times, as has Lille’s Sidibe.
The Frenchman, 23, has featured for LOSC in every one of their league matches this season and is able to play at both left and right-back.