More specifically, and in layman's terms, Weaver was told some nerves tightened up around his neck, which may have played a part in him topping out at 81 mph and serving up three home runs in 2 2/3 innings against the Dodgers on Wednesday.
"The third homer that I watched go out kind of hurt my neck a little bit," Weaver joked.
The Angels starter was scheduled to meet with Dr. Robert Grumet, the team's orthopedic physician, on Friday to get more specifics and potentially map out a recovery schedule.
For now, Weaver will keep playing catch to stay ready for the start of the season.
"I just feel like it's neck tension that is causing me to not be able to throw the ball like I want to," Weaver said. "I guess it's going to kind of help to get a professional doctor to go from there."
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Some form of neck tightness has "always been there," Weaver said. "I just didn't think it had anything to do with the throwing motion."
Weaver spoke to former teammate and current Dodgers starter Scott Kazmir, who dealt with similar -- albeit milder -- neck issues while recently making his way back to professional baseball. Kazmir suggested dry needling, which uses acupuncture needles to help alleviate muscle pain.
Weaver went to a handful of sessions over the offseason, then stopped.
"It was great, the girl I was working with was awesome, but it just got a little bit too weird for me," Weaver said. "Something about putting needles in your neck that I wasn't really too comfortable with."
Weaver said the neck issue is "not painful."
"Just restricting," he said. "It's just not functioning the way that I know it can function."
Weaver, coming off a career-worst season and entering his final year before free agency, spent the offseason dedicated to a strict stretching regimen in hopes of rekindling some of the life on his fastball. At one point, Weaver said, he called his manager, Mike Scioscia, to tell him, "I think I'm back."
"There was a week where throwing was going great," Weaver said, "and through this process, there's just good and bad days."
But Weaver has yet to see results translate to games. He threw two scoreless innings against the Cubs at Sloan Park in his Cactus League debut on March 4, but he topped out at 83 mph, one or two ticks slower than his average last season. Five days later, his fastball sat mostly at 79-80 mph.
"I think every pitcher pitches with something, and Weave has shown over the course of time to be able to adapt and pitch when he's not 100 percent," Scioscia said. "But we want to make sure that this is something that if you do need to grind through, great, he will. If it's something he needs some time to let it calm down, that's where we'll go. But we're going to wait for the medical staff on that."
• Angels first baseman C.J. Cron is 4-for-19 in Cactus League play and will spend Saturday morning getting some extra work on the Minor League fields. Scioscia said Cron "doesn't have his timing right now, but he'll be fine."
• All 22 of the Angels' pre-arbitration players have agreed to their 2016 salaries. There were no renewals. Teams determine the salaries of their Major League players until they reach arbitration. The minimum this season is $507,500.
• Tony Clark, executive director of the Major League Baseball Players Association, will continue his tour of Spring Training ballparks by meeting with the Angels on Saturday morning. C.J. Wilson is the Angels' MLBPA representative.