The Englishman opened the scoring in a 3-1 win at the Britannia Stadium but had to be withdrawn 15 minutes from time.
However, Lambert is confident that the striker will be fit for the club's next game against Fulham.
He said: "Gabby was outstanding. He hurt his thigh a little bit but hopefully he will be okay."
Three points took Lambert's side out of the drop zone into 16th place.