Klaassen played for the first time in almost three months after turning out for Everton's U23s.
“I thought he was okay," said Unsworth.
“I thought he worked really, really hard, I thought he was honest in his performance.
"He was talking to the young players and he hasn't played for a long, long time so for him to get 70 minutes under his belt, he was delighted.
“He's a wonderful professional and we're delighted to have him with us and he'll get better.
“He needs to play games, his attitude was great and he showed one or two nice touches."