In his rookie season, Lance McCullers proved to vital piece to the Astros rotation. Going into Spring Training, he was locked in as one of the team's starting rotation. Those plans will have be revised as McCullers is dealing with shoulder soreness and is likely to miss the start of the season.

Hinch on McCullers: "It's becoming unlikely that he'll be breaking with our team healthy." — Julia Morales (@JuliaMorales) March 15, 2016

The soreness became public on Friday as a scheduled bullpen session was pushed back as reported by MLB.com's Brian McTaggart. McTaggart noted in the article:

Hinch said McCullers didn't feel as well as he would have liked after throwing on the side Friday, and that he would have his scheduled bullpen session pushed back a couple of days. Hinch said McCullers would be sent to see a team doctor.

An MRI exam on Saturday confirmed there was no damage as reported by the Houston Chronicle's Jose de Jesus Ortiz.

"The MRI came back 100 percent clean," (McCullers) said. "I'm fine. I'm just going to have to deal with the soreness day to day. There's no real timetable."

Astros general manager Jeff Luhnow said on Sunday there was no timetable for McCullers getting back up to speed.

"We want to give him a little bit of rest," said Luhnow. "We want to make sure he doesn't have any tightness."

So at the moment, it is not defcon one with Lance McCullers. But there are plenty of reasons to be cautious with the young righthander.

McCullers is feeling soreness after pitching 157 2/3 innings last season, over 50 more innings than he has thrown in his previous three seasons in pro baseball.

The Astros picked up starter Doug Fister for this exact reason. The question on who be the odd man out in the Astros rotation at the start of 2016 becomes irrelevant as Fister slots in for McCullers. The focus for McCullers can then be on being ready and healthy for a possible playoff push.