The talented forward was given a four-to-six month timetable following shoulder surgery after he was injured Dec. 30.
"If you take the shortest period, that would be the end of April," Rutherford told reporters Wednesday, according to the Pittsburgh Post-Gazette's Mike DeFabo. "I would expect, knowing Jake Guentzel, that he's going to be ready."
There haven't been any setbacks in the 25-year-old's rehab, Rutherford added.
Guentzel was leading the Penguins in scoring when he was injured, collecting 20 goals and 43 points in 39 games. The Nebraska native is coming off a 40-goal season in 2018-19.
He inked a five-year, $30-million contract extension with Pittsburgh in December 2018.