@HighEliteMajor, after digesting it here is what I come up with: be very concerned that some kind of serious knee injury beyond a knee sprain has already happened. Be concerned that Joel was possibly sent back out in a blow out to fake being okay as best he could briefly in order to mask the degree of the injury for the upcoming game.
Joel appears a very tough young man. He has already appeared to play through pain. He recently played through what appeared a significantly limiting eye injury and he has appeared to be able to take a lot of obvious physical punishment already, so we can reasonably infer he has a high pain threshold. And we know Self has some history of masking significant knee (and other) injuries either through initial non disclosure, or understatement.
Kaun--knees that apparently needed surgery but were played through.
Aldrich--apparently some kind of leg injury that was apparently never really disclosed that I can recall.
EJ--some kind of knee injury that lead to a surgery that was apparently played through.
Rush--part of a knee surgery rehab that appeared to be played through.
Selby--reputedly playing in a boot.
Releford--reputedly playing in a boot.
Taylor--reputedly playing a season on a scoped knee only 10 days after a scope.
And this year, if I recall correctly, Selden had an early undisclosed knee injury that was apparently played through and now, after two blazing 20 pt plus performances, now may have recurred and induced a couple of muted performances.
None of the above encourages optimism about the potential mildness of injury to Black's ankle. Black missed an entire game with a boot on. We know guys in the past have played in boots. Plus that boot looked like the kind you get for a broken ankle, or some damaged ligaments or tendons to this layman.
Nor does the above encourage much optimism about the likelihood of Embiid having only a slight sprain. Would Self even mention a slight sprain before a big rematch with ISU other than to play around with Hoiberg? Probably not. Hence, my two hypotheses: a) playing around with Hoi; or b) something more serious than a slight sprain.
If the guys listed above were playing through injuries that needed surgery, some without missing any games, often with only being characterized as "a little nicked up," then seeing Black sitting out an entire game in a boot suggests something that perhaps cannot be effectively scoped, and something that could persist quite some time.
And Self just hinting at Embiid being worse than thought, when he was sent back out on the floor unnecessarily in a blowout makes me wring hands.
Time will tell one way or the other, of course.
But the truth remains: in a worst case scenario of Embiid and Black being finished, Traylor and Lucas and Wesley and Mickelson can be pressed into duty, and this can be turned back into a Kemba/Carmelo kind of team with everything going through Wiggins.
This Kemba/Carmelo kind of team would be much more encumbered by Selden having a serious, persistent and apparently no longer talked about knee issue.
So: if we see Greene's, or Connor's, or White's minutes ramping up precipitously the next few games, we can perhaps infer not only that Selden has health problems that are not expected to resolve during the season, but more significantly that Self is perhaps restringing the team into a Kemba/Carmelo kind of team in which the team is put on Wiggins back, and we play with bigs who's only role is defense and rebounding. That kind of a team would have to have a trey shooter on the floor at the wing opposite Wiggins that the present stringing of the team lacks with Selden (most games).
If I recall correctly, Carmelo's ring team and Lute Olson's ring team at Zona made due with long, non NBA grade bigs not sharply better (though probably more experienced) than Traylor, Lucas, Wesley and Mickelson, because they had a Carmelo, or a Mike Bibby on the perimeter and a couple of reliable trey dingers along side. Can't recall Kemba's cohorts as well, but maybe you can.
Anyway, the season started out depending mostly on how good Wiggins could be. So: in a worst case injury scenario with Black and Embiid out for good, the team merely defaults back to that.
Imagine the oddsmakers in Vegas sweating bullets about all this right now. They are the guys with huge bones at stake here. :-)