Despite Pardew saying he is trying to get the Spanish left back to stay, Enrique is expected to leave Newcastle for Liverpool this week in a £5.5m deal.
Pardew flew out to watch Pieters, 22, play for PSV Eindhoven in their 3-1 defeat at AZ Alkmaar.
Pieters is recovering from a pre-season knee injury.
He came off the bench to play the second half in PSV’s defeat.