"Shelley hit Boyce squarely from behind into the glass," Shanahan said. "Boyce's back was turned toward Shelley well before the contact, requiring that Shelley avoid or minimize the check. He did neither."
Shanahan said Shelley's two suspensions last season "weighed heavily" on his decision.
Reached at home, Shelley said he expected to be penalized but was "definitely" surprised at the length of the suspension. He added that Shanahan "set the tone in a sense" for how he will handle disciplinary matters this season.
Peter Luukko, the president of the Flyers' parent company, Comcast-Spectacor, said the league was showing it was "trying to get serious" about these type of incidents. "When it's your own player, you always think it's wrong," he said of the suspension's length. "The important thing is that it's consistent all year."
Shelley will be permitted to practice with the team during the suspension.
"Camp is all about getting into team mode," he said. "Now I'll just practice and try to help out in other ways."
The suspension could open the door for 6-5, 228-pound left winger Tom Sestito to open the season with the Flyers. (Zac Rinaldo, who is 5-11, 180 pounds, is considered a middleweight instigator.)
Game stuff. James van Riemsdyk scored two goals - one on the power play - but the Flyers fell to 1-2 in the exhibition season, dropping a 4-3, shootout decision to the Detroit Red Wings at the Labatt Centre.
Ian White scored the game-winner on the eighth shot. The Wings had a 2-1 edge in the shootout.
Trailing by 3-1, the Flyers scored two goals in the final 2 minutes, 45 seconds to send the game into overtime.
Van Riemsdyk's power-play goal made it 3-2 with 2:45 to play, and Wayne Simmonds tied it with 52.3 seconds left. Simmonds scored from behind the net when his pass deflected off a Red Wings player.
Detroit, which finished with a 41-30 shots advantage, took a 2-0 lead against goalie Michael Leighton (38 saves), scoring on Darren Helm's shorthanded goal in the first period and on a Valtteri Filppula deflection of a midair pass in the second period.
Breakaways. The Flyers sent smallish left winger Tomas Hyka back to his junior team in Gatineau. Hyka (5-10, 158), 18, has been impressive in camp, but he was not eligible to be signed as a free agent because he played in Europe last year. If he had played in North America, he could have been signed. . . . The NHL will formally - and finally - announce Monday that the Jan. 2 Winter Classic between the Flyers and Rangers will be at Citizens Bank Park. A news conference will be held at CBP.
Contact staff writer Sam Carchidi at firstname.lastname@example.org or @BroadStBull on Twitter.