Colts QB Andrew Luck is dealing with a partially separated shoulder, or a "subluxation," according to Indy Sports Central's Chris Hagan.  The major concerns at this point are "pain and arm strength," Hagan adds.  Luck has reportedly consulted with at least 3 different experts for a diagnosis and rehab plan.  Per Dr. David Chao, a former NFL head team physician, Luck's timeline for return depends largely on whether his labrum is torn.  Chao adds that rehab for this injury is generally measured in "weeks, not days."  It sounds like Luck is nowhere near a lock to play against the Texans on Thursday night.  Stay tuned for updates.

ESPN's Adam Schefter reports that Colts QB Andrew Luck has decided to retire. Luck has reportedly already talked to team management about his decision. Jacoby Brissett now takes over the starting gig. This appears to be a shocking move to everyone. Schefter reports that Luck feels "worn down." The QB switch lowers the ceiling for everyone in the Indy offense. The Colts finished 30th in points and 31st in scoring in 2017, with Luck sidelined (shoulder) and Brissett starting.

Here's a full breakdown of the fantasy impact of Luck's retirement.

Colts HC Frank Reich said Tuesday that QB Andrew Luck (calf/ankle) won't practice this week. Luck is still struggling with "full speed movement vs. pain threshold," per Reich. So the earliest Luck will get back on the field is next Monday -- 13 days before the season opener. He's looking legitimately questionable for Week 1. QB Jacoby Brissett will start if Luck isn't ready.

ESPN's Chris Mortensen hears that there's "guarded optimism" that Colts QB Andrew Luck (calf/ankle) will be ready for Week 1. That pretty much matches what we heard from GM Chris Ballard on Wednesday. Luck certainly isn't a lock to be out for the the opener against the Chargers, but we get the vibe that he's better than 50/50 to play Week 1. Luck's ADP has dropped to the 8th round in drafts over the past couple of days.

In a conference call with reporters on Tuesday, Colts GM Chris Ballard refused to say that QB Andrew Luck will definitely be ready for Week 1, according to The Athletic's Zak Keefer. Ballard also gave some more details on what's ailing Luck, explaining that the original calf strain has turned into a "high-ankle-like issue." Ballard added that there's no plans for surgery. The Colts medical staff is trying to pinpoint the source of the pain and have Luck rehab. Beyond the fact that this has been a problem since the spring, it's troubling that the team still doesn't seem to know exactly what's wrong with its star QB. It's turned Luck into an extremely risky fantasy pick -- at least until we see him back on the field.

Colts owner Jim Irsay said in a Monday interview on SiriusXM that QB Andrew Luck is dealing with a "small little bone" issue. “But I really feel very confident that he’s going to find his way through this thing," Irsay added. It's the 1st we've heard of any sort of bone problem for Luck and adds more mystery to an injury that's lingered since the spring. Luck's ADP has sunk to the 7th round in drafts over the past week, but he's still a general avoid at that price.