Per Sportsnet's Chris Johnston, the three-game ban will cost Komarov $47,580.64 in salary.
The incident happened late in the first period of Thursday night's game in the Maple Leafs' zone. With McDonagh having gotten rid of the puck, Komarov came in from behind the play and hit the defenseman up high with his elbow.
Sportsnet showed the replay:
The officials handed Komarov a major penalty and ejected him from the game. He had a phone hearing with the league Friday, per Pat Leonard of the New York Daily News.
It was the second time this month that McDonagh was on the wrong side of a dirty hit. The Rangers captain had recently missed four games after suffering a concussion when Philadelphia Flyers forward Wayne Simmonds punched him Feb. 6.
Komarov's actions riled up WFAN 660's Sean Hartnett:
Can't say I have any respect left for Leo Komarov. He's fully aware of McDonagh's recent concussion. He knows what he's doing. Disgusting.— Sean Hartnett (@HartnettHockey) February 19, 2016
The 29-year-old forward is in the midst of a breakout season in his third year with the Maple Leafs. After recording 12 goals and 23 assists in his first two years, Komarov leads the Maple Leafs with 18 goals and 17 assists in 2015-16.
His emergence earned him a trip to the All-Star Game this season.
After Thursday's incident, though, Komarov may be playing with a target on his back. Luckily for him, the Maple Leafs won't play the Rangers again this season. With a 20-27-9 record, it's unlikely that they'll make the playoffs to set up a possible postseason matchup, either.
Stats courtesy of Hockey-Reference.com.