TEMPE, Ariz. -- Angels right-hander Griffin Canning provided some clarity on Saturday about the “biological injection” he received in his right elbow Friday, saying it was a platelet-rich plasma injection and he’ll be reevaluated in three weeks.

Canning, who felt tightness in the elbow after throwing two scoreless innings against the Dodgers on Feb. 26, underwent an MRI exam last week and received a second opinion on Thursday. He flew to Los Angeles on Friday to receive the injection and said he felt sore, but he otherwise was optimistic about returning this season. He also explained that surgery was never on the table because his ulnar collateral ligament is not torn.

"There’s no joint, no ligament issues," Canning said. "It’s just kind of some stuff rubbing against each other in there, so hopefully I’ll just get this injection and get some of the inflammation out of there and then get going."

Canning was shut down twice last year with similar elbow issues and is hopeful that the injection will help him get past them. His MRI exam revealed “chronic changes” to his UCL and not a tear, but Canning said it has been tough figuring out what the issue was. He said doctors now believe the issue stems from tissues rubbing together.

“I think we can really feel good about what’s going on in there,” Canning said. “Obviously, this is the best option for me right now after talking to these other doctors and our training staff.”

Canning, though, will open the year on the injured list after being projected as the club’s No. 4 starter behind veterans Andrew Heaney, Julio Teheran and Dylan Bundy. He is coming off a solid rookie year, posting a 4.58 ERA with 96 strikeouts, 30 walks and 14 homers allowed in 90 1/3 innings.

Angels manager Joe Maddon met with Canning and said they’ll have to take a wait-and-see approach, as they’ll know more closer to Opening Day. Canning will have a better sense of how the injection is working by late March or early April.

"When I talked to him, he's pretty optimistic as well as me,” Maddon said. “I don't have much other than the fact that nobody has told us anything horrible. Just play along with the medicine and take it from there. I really believe that he wants to get back out there, and that matters a lot.”

With Canning out of the mix, the Angels now have two spots up for grabs at the back end of the rotation. Right-hander Matt Andriese now has a much better chance of being a starter than a reliever to open the year, while the Angels also have several youngsters in the mix, including right-hander Jaime Barría and left-handers Patrick Sandoval and José Suárez. Left-hander Dillon Peters also impressed Maddon on Friday and will continue to be stretched out as a starter.

Andriese, Barría, Sandoval, Suárez and Peters have all pitched well this spring, posting a combined 0.86 ERA in 31 1/3 innings in Cactus League play. Barría entered Saturday as the only pitcher in the Majors who has thrown at least nine innings without allowing a run.

“Our pitching's been good,” Maddon said. “We only had a couple bad innings this whole camp. As the pitching goes, with good health -- they need experience. They're going to have some rough moments, no question. But physically, talent-wise, it's there. It's absolutely there. And now these guys have to get comfortable in their Major League skin and perform. But the ability's definitely there."