At the age of 20, the Flyers' Ivan Provorov isn't just blossoming into one of the NHL's best young defensemen.

Now in his second NHL season, he's also becoming a mentor of sorts to the many inexperienced players on the team's Baby Blue Line.

Exhibit A: The Flyers' 4-3 overtime loss Monday to Arizona.

After Travis Sanheim's miscue at one end of the ice led to an odd-man rush and Arizona's winning goal, Provorov sought out the rookie defenseman and gave him some comforting words.

"Stuff like that happens," Provorov said after Tuesday's practice in Voorhees. "There will be games that you'll be minus-whatever. Did you see [Ottawa star Erik] Karlsson was minus-6 [Monday] night? The game in Chicago last year, I was minus-5. Those games are going to happen."

Provorov's message to Sanheim: Everybody makes mistakes, and you just have to learn from them.

Provorov did that last year after the game in Chicago — which happens to be where the Flyers will play on Wednesday night — and became the team's best defenseman.

That game in Chicago was the third in Provorov's career.

"It was a good learning experience," said Provorov, who Tuesday had three assists, fired seven shots, blocked three shots, and played a staggering 28 minutes and 7 seconds.

Sanheim, 21, appreciated Provorov taking him under his wing.

"He just said he's been in that situation and had some misplays earlier in his career as well," said Sanheim, who was minus-2 on Tuesday and is minus-6 over his first nine games. "I'm just trying to build on my game. You can't dwell on a mistake."

While turnovers have plagued Sanheim, he has shown the ability to jump into a play and create offense.

"I think overall, I've started to make better plays with the puck, and looking a little more confident and doing things more like what my game's all about," he said. "But obviously there's going to be little things we go over with the coaching staff that I need to build on and work into my game."

Because of injuries to Shayne Gostisbehere and Andrew MacDonald, Sanheim is one of four Flyers defensemen who are rookies after playing last season with the AHL's Phantoms. The others: Robert Hagg, Mark Alt, and Will O'Neill, 29, a journeyman minor-leaguer who was recalled Tuesday and is expected to be an extra player on the road trip that has stops in Chicago and St. Louis on consecutive nights.

"There are some familiar faces and it's nice to see those guys around," Sanheim said. "It just goes to show the good group we had down there last season, and the guys who are capable of coming up and providing depth here."

In another matter, general manager Ron Hextall said defenseman Samuel Morin's unspecified injury is worse than first anticipated. Hextall said Morin will miss about two weeks. Morin had been slated to join the Flyers for Monday's game against Arizona, but his recall was terminated when Hextall learned of his injury.

"Sam's a tough guy, and he didn't disclose 100 percent of his injury because he plays through things," Hextall said. "He has a little nick that's going to keep him out a bit — not days, maybe a couple weeks."

The 6-foot-1, 190-pound O'Neill, signed as a free agent before last season, had three goals, 28 assists and a plus-1 rating in 57 games for the Phantoms last season and was a key cog on the power play. In nine games this season with Lehigh Valley, O'Neill had a goal, two assists, and a plus-5 rating.

Drafted in the seventh round by the Atlanta Thrashers (remember them?) in 2006, O'Neill has never played in an NHL game.

"I'm excited," said O'Neill, a Boston native who has spent the last six-plus seasons with three AHL teams. "It's been a long time coming for me."

Breakaways. Nolan Patrick and Gostisbehere skated before the Flyers' practice. Though they are listed as day to day with apparent head injuries, they will not make the road trip. Instead, they will work out in Voorhees. … MacDonald is making progress and might be back in a less than three weeks, Hextall said. … Dating back to last season, Sean Couturier has 32 points and is plus-28 in his last 32 games.