Santon welcomes raft of Newcastle signings
United signed six players during January - arrivals who have coincided with a run of two wins in three games.
"They've only played two or three games but it's like they've been here for a year," Santon told BBC Newcastle.
"We've grown in confidence, we understand each other, we're a really strong team and we are competitive."
Santon added: "The atmosphere among the players is really nice."