Seguin, second in the NHL in points (59) and third in goals (29), was helped off the ice after being checked in the lower leg by defenseman Dmitry Kulikov in the third period of the Stars' 2-0 win over the Florida Panthers.
The circumstances of the injury to Seguin, the team's scoring leader, bothered the Stars.
"It's a dirty shot," Ruff said of the hit, on which Kulikov went low against the unsuspecting Seguin. "You end up taking your best player out. Not only out of the game, but he's taken him out of the lineup for a little bit. We'll let the league deal with it ... It's just a shot that didn't need to happen."
Vernon Fiddler was more adamant.
"(Seguin)'s released the puck, and he comes across and takes his knee out. It's a gutless play on his part, and we'll have to deal with that at a later time," Fiddler said.
Panthers coach Gerard Gallant disagreed with the Stars' assessment.
"It was the right call. It was a five-minute [major] and game misconduct, so there's no issue," he said.
Stars forward Patrick Eaves followed Seguin to the locker room 51 seconds later after teammate John Klingberg's wrist shot hit him in the head.
In addition, forward Ales Hemsky left in the first period with a lower-body injury.
Ruff was left with a grim injury report. None of the three injured players accompanied the team to Colorado for Saturday night's game.
"Eaves is on the way to get X-rays. He took a pretty good shot there to the head. He has had a previous injury there, so we're fairly concerned," Ruff said.
"Tyler is going to be re-evaluated (Saturday). It looks like he's going to miss some time, too. Hemsky's going to miss some time."
The Associated Press contributed to this report.