Pompey snapped up the former Liverpool goalkeeper after he spent four years in Spain with Real Sociedad and a brief loan spell at Mallorca.
Many pundits believe he was unlucky at Anfield - he was allowed to leave after the Reds won three trophies in 2000-01.
Goalkeeping coach Hans said: “He went to Real Sociedad and did particularly well over there and now he’s back in the Premiership.
“I’ve read articles on him and he’s delighted to be back in the Premiership again - I think he’s a very good goalkeeper and he might just prove a few people wrong.
“To come to England as a foreign goalkeeper isn’t easy because the game is so different from the continent. If you see the overall picture he’s a very good goalkeeper and I think he won four or five trophies with Liverpool, so he can’t have done that badly!
“When he was on the bench at Liverpool I spoke to him, we talked about different things and he told me there was interest from a Spanish club and he wanted to go and play. I thought that was a great attitude.”
Hans Segers has a hunch Sander Westerveld will want to prove a few people wrong on his return to the Premiership with Portsmouth.