Moreno is convinced that each of these signings will make a positive impact at Anfield this term, and the Spaniard has been particularly impressed by Keita's efforts so far.
"With both Naby and Fabinho and now Shaqiri, we've brought in top, top players," Moreno told the official Liverpool website.
"Everybody knows that Fabinho is a great midfielder, and from what I've seen of Naby in training, he's just incredible! As we say in Spain, he's a real pitbull.
"I'm still to see Shaqiri but everyone knows him well for his stats and his Premier League record, and how well he performs.
"I think they are three guys who are going to entertain the fans and give us an awful lot this campaign."