The defender made 20 Premier League appearances during a loan spell at Sunderland last season, but has now made the permanent switch to Newcastle, signing a three-year contract with the Magpies.
However, despite his top flight experience, not every member of the Toon Army was thrilled to have secured the defender’s signings, with fans taking to Twitter to voice their feelings.
Manquillo has become Newcastle’s fourth summer signing following the arrivals of Christian Atsu, Florian Lejeune and Jacob Murphy.
Benitez’s men also take on Germans outfit Mainz and Wolfsburg, along with hosting Serie A club Hellas Verona a week before the season starts.
Manquillo put pen to paper on a three-year deal at the newly-promoted Premier League club, who snapped up the right-back for an undisclosed fee.
The former Liverpool boss also explained why he chose to add Manquillo and Murphy to the squad, explaining the pair fit specific requirements the Magpies had.
“When I went from Real Madrid to Atletico, I was very young, so making that change was different”, said the right-back told NUFC TV.
“He can still improve but he has played for Spain at Under-21 level and that is because he is a good player, so hopefully he will show that form here”.
“From the first moment my team-mates have welcomed me and tried to help me to adapt as quickly as possible”, said Manquillo.
“More recently I played for Sunderland, but now I’ve got the opportunity to join this big club, the biggest in the North East“.