1) The Flyers announced on Sunday that veteran defensemansuffered a lower-body injury during training and will miss approximately six weeks. Assuming the injury occurred in recent days, that would put MacDonald's return timeline at some point in late October. The alternate captain averaged 19:51 of ice time last season.2) MacDonald's injury increases the chances that second-year procould make the Flyers' opening night roster with a strong camp. The automatic assumption by some is that recently signedwill jump into the starting six to start the season and the Flyers will use a fill-in seventh defenseman (such as Phantoms veteran, who has some NHL experience) until MacDonald gets back. However, there will be competition for the spot in weeks to come.Both Myers and Folin are righthanded shooters. The advantage that Myers brings, if he has a good camp, is superior skating and natural puck skills compared to Folin. Assuming the top pairing ofandremains together, having all three amongand Folin in the same lineup means that of them will be a pairing and the other will play with second-season NHLer. That's a bit too much overload on physicality/size. Flyers head coach stated late last season that he did not like the chemistry of Hägg with Gudas during their brief time together.Last season, Sanheim saw considerable time with Gudas in the first half of the season, although he was more effective on a pairing with MacDonald in March following Sanheim's return to the big team after a short-term demotion to the AHL. If Myers makes the team, it opens up a wider array of potential pairings compared to Folin. If Folin beats him out, I'd think the highest probability favors a pairing with Hägg (not just because both are Swedes, but because Hakstol pulled the plug quickly on a Hägg-Gudas pairing).Something else to keep in mind: Last season, the Flyers had two rookies on the blueline who played 50+ games if playoffs are included (49+4 for Sanheim, 70+2 for Hägg). Overall, the Flyers had two rookies (Hägg and center) who appeared in 70+ games, three who appeared in 50+, four who played in 39+ (39 regular season games for winger), five who played in 25+ (23+4 for left winger) and six who played in 11+ (if goalie11 regular season appearances are also counted). Add in second-year NHLers Provorov (82+6) and(81+6) and there was a lot of youth in the lineup throughout the season, despite the frequent public criticism of Hakstol's usage patterns of many of these players.This season, however, Lindblom is the Flyers' only near-lock rookie. He still qualifies as a rookie under NHL rules, which is why he is also attending Rookie Camp. As such, there is a little more breathing room to potentially add a rookie such as Myers into the blueline mix.During Development Camp in July, Flyers defense development coachopined that Myers isn't quite NHL-ready yet, largely because he missed most of the first half of the 2017-18 AHL season due to injury. General managerpraised Myers' rapid adaptation to the AHL and all the minutes he played during the Calder Cup playoffs (including playing 60+ minutes in the Phantoms' five-OT game in Charlotte on the nighttore his ACL in the first period).However, Hextall also stopped short of saying in July that he felt Myers is ready to immediately push for an NHL job. He did say Myers would get the chance in camp to prove himself, which is a degree higher than him saying that 19-year-oldwould not only have to perform well in camp but also outplay veteran options to have a shot an NHL spot.With the news of MacDonald's injury, Myers' camp performance becomes more of a focal point. There is no doubt that his upside is higher than Folin's and that he'd diversify the skill-set mix on defense. The question now is of showing his readiness to step up into a starting role. He likely won't be retained as a number 7, even if it is only for a few weeks until MacDonald is back.3) On the Flyers official website, I wrote a five-point Rookie Camp preview. Note: The article was completed before news of the MacDonald injury changed the outlook somewhat for Myers, but he'd have been in a leading role at Rookie Camp in either case.4) On-ice work at the Flyers rookie camp starts at 11 a.m. ET on Monday at the Skate Zone in Voorhees.5) Sept 10 Flyers Alumni birthday:(1969). Sadly, 2018 has been a heart-wrenching year for the Joseph family, as Chris and Andrea's son, Jaxon, was one of the Humboldt Broncos players who perished in the horrific team bus accident on April 6.