Jackett said that he was especially pleased for 20-year-old striker Marquis, who scored the winner in the last minute of normal time.
"I thought it was a terrific performance from the whole team," said Jackett.
"We deserved to win and I was so pleased for John Marquis that he got the winning goal. He has been out for a long time and has worked so hard to get back to fitness."
Marquis had made just one appearance from the bench before starting in tonight's match.