The German international scored twice in the 4-0 win over Barcelona on Tuesday and his former coach Ismael says he is making great strides towards showing his true potential as a player.
Ismael told kicker he "knew the French league would be a great fit for him."
He added: "It is nice that he can perform at this level now as well.
"He already showed here that he can do it."
Draxler, who will be back in domestic action against Toulouse at home in Ligue 1 on Sunday, has said he settled into life in Paris from the minute he arrived at the club last month.
He told Die Welt: "Since my first day in Paris, I have been fully happy.
"After a difficult spell at Wolfsburg, I have started again from scratch.
"Paris is a fascinating city and this club is perfectly organised. In joining PSG, I made the best possible decision."