The 21-year-old was in inspired form in Sunday's defeat to Manchester City and Vermaelen admits he will be a key figure during a challenging run of fixtures.
"I think Jack did well," the captain said. "For him and for Abou [Diaby] it was not easy with 10 men, they had to run a lot. Jack did well and he worked hard.
"You can see that since he came back he is growing and growing. And I think at the moment he is at a good level.
"He is a world-class midfielder and he can only get better because he is young, coming back from more than a year out with injury. So I am very confident he will come back really strong."