Werner concedes now Real Madrid fullback Alexander-Arnold informing them of his decision was a heavy blow.
"We do respect the fact that Trent has moved on,” Werner told the Liverpool Echo. “I told someone recently this story about seeing Trent on the last weekend of the season, with Billy (Hogan, chief exec) and I just wanted him to know from me personally we are and were as a club thankful for all his contributions.
"He showed me a picture when he was seven years old, when he was a young kid at the academy, and I have a lot of fondness for all that he has done and so it is time for him to move and time for us to replace him.
"We do wish him well and I understand the emotions of supporters who were disappointed and we were disappointed too but it is overshadowed by my wonderful memories of him.
"I'll never forget that pass he made, the corner he took, for the fourth goal against Barcelona. That was just a work of genius and as a football fan, watching some of his assists, the way he would pass the ball 30-plus yards to a specific point and create a goal was just...no wonder Real Madrid are delighted!"