Wirtz, 22, joined Liverpool for a then British transfer record of £116 million, but is yet to register a goal or an assist in a competitive game.
Simons, 22, who was also signed from the Bundesliga, is in a similar boat, although he did manage to get an assist in Tottenham’s 3-0 Premier League win over West Ham.
Speaking ahead of Spurs’ Champions League clash with Monaco on Wednesday (October 22), manager Thomas Frank compared the two.
"Very good comparison with Wirtz, also a very good player, just like Xavi, coming into a new country, new club, new city, just need to settle and it is part of it,” he said.
“We are all getting judged every game, but we also need to see the bigger perspective. I always look for glimpses, and Xavi, I asked him to be more arriving in the box, and when I looked back at the game, he did.
“Was there a big eye-catching moment? No, but there were glimpses, so it’s going a little bit in the right direction."