The Swede bagged his 17th career hat-trick and his first in a United shirt to all but seal his side's place in the Europa League round of 16.
But the French team made life difficult for the Jose Mourinho's side.
And Ibrahimovic feels United can do more.
Manchester United player ratings against Saint-Etienne in Europa League
Thu, February 16, 2017
Express Sport brings you Manchester United's player ratings against Saint-Etienne in the Europa League
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Express Sport brings you Manchester United player ratings against Saint Etienne
Manchester United's Zlatan Ibrahimovic celebrates scoring his hat-trick
He said: "We created good chances.
"It was important to get a good win at home and we bring it with us in the second leg. It was a good game but I think we can do better.
"Every time I've played against Saint-Etienne, with hard work there has been a couple of goals. I've scored a couple of goals tonight and hopefully I can do the same next week."
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