JUPITER, Fla. -- Though a second read of an MRI on his right shoulder revealed no new injury, Carlos Martinez is in jeopardy of opening the season on the injured list after having his rehab program extended by a week.

That decision came on Monday with Martinez’s choice to receive a shot of platelet-rich plasma during a visit to the Andrews Institute for Orthopaedics and Sports Medicine in Pensacola. Initially expected to resume throwing next Tuesday, Martinez must now wait an extra week before doing so.

That would leave Martinez, who returned to Cardinals camp with his right arm in a sling, just over two weeks to prepare for Opening Day.

“It obviously is more impactful,” manager Mike Shildt said when asked about the timetable. “We’ll evaluate it in two weeks. Now, his competition is his rehab.”

Martinez was shut down from throwing last week after feeling weakness around his right shoulder during bullpen sessions. At the time, the Cardinals moved Martinez into a rehab program that targeted strengthening the muscles in that area. It was Martinez’s decision to seek a second opinion of his scan.

“Good news is that the second opinion validated the first opinion,” Shildt said.

After the Cardinals see how Martinez responds to the injection and rehab program, they will re-evaluate his potential role for the 2019 season. Though Martinez entered camp prepping to be a starter, the organization has not ruled out utilizing him in a relief role. That could speed up his readiness for the season, but would also require Martinez to show that he can recover quickly between appearances.

Then there is the bigger task of staying healthy. Martinez, who first had issues with his throwing shoulder in 2015, landed on the injured list three times last season. Thought the injuries were different, the Cards suspected that the source was the same. That’s why concerns about Martinez’s shoulder strength early in camp prompted the club to press pause on his spring program.

In the meantime, competition around Martinez moves forward. With a job in the rotation now open, the Cardinals will audition a handful of young starters over the next month. 

Dakota Hudson and Austin Gomber will take the mound for their Grapefruit League debuts on Wednesday. John Gant and Daniel Ponce de Leon are also considered rotation candidates. Gant, as an out-of-options player, may be the early favorite to snag the open spot.

Alex Reyes, whose return from a second right arm surgery has proceeded without a hiccup, could push his way into the mix, too, depending upon how the Cards decide to map out his innings. There is no indication that the Cardinals are about to change course and look to sign a starter still available on the free-agent market.

“A lot of good competition in camp,” Shildt said. “The depth is huge.”