When he arrived for a sit-down with Chuck Fletcher in June, for a face-to-face meeting as part of the Flyers’ courtship of him, Kevin Hayes knew little about the depth and breadth of the franchise’s recent rebuilding period.

Hayes had been a New York Ranger for five years. His only firsthand exposure to the Flyers and their infrastructure had come in some train-in, train-out trips for games at the Wells Fargo Center. There was no time or opportunity to learn anything. “They were in the same division,” Hayes said late Thursday, “and we were told to hate this organization. So I didn’t know much.”

During his two-hour meeting with Fletcher, though, Hayes got a crash course in the measures that Fletcher’s predecessor, Ron Hextall, had taken to grow a flourishing farm system on what, for nearly a decade, had been barren soil. Fletcher provided Hayes with a likely projection of the 2019-20 Flyers roster, and while Hayes was impressed with Fletcher’s presentation, it wasn’t until after he signed with the Flyers and showed up at training camp that he grasped just how far they’d come.

“It was shocking at the beginning of the season,” he said, “the depth we have.”

They’re not nearly so deep now, and that misfortune has been the nimbus hovering over the Flyers for the past three months.

By all rights, this should be an encouraging, hope-filled season for them so far. Their easy 6-1 victory over the Buffalo Sabres on Thursday night raised their record to 19-11-5. Travis Konecny has become their leading scorer. Goaltender Carter Hart has met every expectation. Nevertheless, when Fletcher and Hayes reviewed that projected lineup, it’s safe to assume there were three names on it then that, for the worst of reasons, aren’t on it now.

Defenseman Sam Morin, the franchise’s first-round pick in 2013, tore the anterior cruciate ligament in his right knee — for the second time in a year and a half — in early November. Nolan Patrick, the No. 2 overall pick in the 2017 draft, hasn’t appeared in a game this season because of what the team has called a migraine disorder. And just last week, forward Oskar Lindblom — a fifth-round pick in 2014, whose 11 goals this season at one time led the Flyers — was diagnosed with bone cancer and won’t play again this season.

Awful circumstances, all, with no blame to be assigned for them anywhere. But purely from a team-building perspective, they reaffirm how right Hextall was to pursue the patient, prolonged rebuild that he did. No, terrible things — a 23-year-old stricken with Ewing’s sarcoma, a 24-year-old with a twice-torn-up knee — don’t happen to every player and every prospect. But anyone who complained about Hextall’s using 4-5 years to replenish the talent within the organization and not rushing that talent to the NHL had to reckon with two inconvenient truths.

One, for too long the Flyers had failed to maintain even an adequate farm system, let alone a robust one. Two, it’s much easier to hollow out a farm system than it is to restock it. There were always going to be promising youngsters who didn’t make the cut for the Flyers, because there are always promising youngsters who don’t make the cut in any professional sports organization. More don’t than do.

That Hextall stuck to his plan for as long as he did, that he held on to and used those draft picks and gave those prospects time to develop, mitigated some of that risk. But he was never going to eliminate all of it.

In the end, maybe the truest measure of this Flyers season, the best standard by which to judge it, is this: It will serve as a gauge of just how well Hextall did his job and how well Fletcher can build on the foundation he left.

Consider: Buffalo selected Jack Eichel with the No. 2 pick in the 2015 draft. He is their captain. He has never scored fewer than 24 goals in any of his five seasons. In fact, he has 24 already this season and was on a 17-game point-scoring streak before a mysterious upper-body injury removed him from the lineup for Thursday’s game. The Sabres, in turn, immediately provided an indication of what kind of team they are without him. That’s how much a player of that caliber — and the chance to acquire him — can mean.

Well, the Flyers had such a chance, and after two seasons of fits and starts, Patrick is a ghost now, no one quite sure when and if he’ll play again. And still, it’s possible, even probable, that the Flyers will return to the playoffs this season, and it’s possible that they’ll last a while once they get there. If they do, it will be, as Hayes said, impressive, especially given the circumstances.