Roenick nailed Modano into the boards, knocking him out of Tuesday's 2-2 overtime tie. Modano's legs gave out under him as he was helped off the ice. He did not return and later complained of headaches.
Stars defenceman Darryl Sydor called Roenick's hit a "cheap shot."
Roenick, 32, was assessed a five-minute boarding penalty, but not ejected. He will miss games against Atlanta Wednesday and Ottawa on Dec. 21. Roenick will also forfeit $83,333.34 US in salary.
Jeremy Roenick has 11 goals and nine assists for the Flyers this season. (CP Photo)
"I would never try to hurt somebody," said Roenick, who has 11 goals and 20 points this season.
"He's a friend of mine. I apologized to him 100 times."
Modano suffered a concussion three years ago when hit by Roenick, then with Phoenix.
Modano, 32, has 13 goals and 22 assists in 33 games for Dallas this season.
Roenick avoided a suspension after delivering a hard shoulder check on Robert Svehla in a 2-1 win over Toronto on Dec. 12. He received a five-minute match penalty when he was called for charging on Svehla.
A match penalty is automatically subject to review by the league, but NHL disciplinarian Colin Campbell reviewed the hit and said that it was clean. Therefore, Roenick was not suspended.
with files from Sports Network