Trading McGinn provided Groulx with roster flexibility.
There are five rookie forwards, each 20, on the roster and each needs ice time.
Anthony Cirelli (6-1, 198), a third-round selection (No. 72) in the 2015 NHL Draft; played six playoff games last season for Syracuse after he finished playing for Erie of the Ontario Hockey League. Mitchell Stephens (6-0, 195), was chosen in the second round (No. 33) in 2015.
Alexander Volkov (6-1, 195) was a 2017 second-round selection (No. 48) and impressed at training camp. Dennis Yan (6-2, 198), is a third-round (No. 64) selection in 2015. Mathieu Joseph (6-1,172) is a fourth-round pick (No. 120) in 2015.
"As we all know, if we want them to get better, they have to play," Groulx said. "Practicing is one thing, but you're learning more in playing."
Cirelli has 12 points (three goals, nine assists) in 22 games, and Volkov has eight points (four goals, four assists) in 21 games. Joseph has eight points (three goals, five assists). Stephens and Yan each have seven points (three goals, four assists).