TORONTO — Among the many things that went awry for the Toronto Blue Jays in Thursday’s home opener — mustering only two hits, allowing a pair of scud missile home runs to Giancarlo Stanton, coughing up seven hits and three runs over 4.1 bullpen innings — the most concerning may be the way the ball was coming out of Josh Donaldson’s hand.

He had zero difficulty swinging the bat or stealing second with a headfirst slide — no trouble corralling hard grounders at third base. But whenever Donaldson threw to first, there was little behind it.

The problem, according to both Donaldson and his manager, John Gibbons, is a bout of “dead arm,” a shoulder issue primarily experienced by athletes who perform extremely specialized and repetitive arm motions — think quarterbacks and tennis players. It robs them of their ability to generate velocity and repeat smooth mechanics, and is commonly caused by overuse.

In baseball, pitchers experience it most often. But it’s not unheard of for position players to go through dead arm periods, as well. Donaldson says he’s never encountered it before in his career, but that he dealt with it off and on throughout spring training.

“It’s just kind of been ongoing, back and forth. I don’t have any pain or anything like that, which is always good. It’s just about getting the strength back,” he said. “Some days it would feel really good, and then the next day, maybe I’m overworking it sometimes. It’s kind of a thing that I’m trying to be cautious with, while knowing when to push it and when not to.”

The issue clearly compromised Donaldson’s ability to throw to first during Thursday’s 6-1 loss to the New York Yankees, as he looked uncomfortable each time he was tested.

In the first inning, he made a diving stop on a 94-mph ground ball off the bat of Gary Sanchez, and made a softer-than-usual throw that bounced on the infield turf but still reached first just in time to nab the runner.

In the fourth, Aaron Hicks shot a grounder back to the mound that kicked off J.A. Happ’s leg and careened in Donaldson’s direction. The third baseman bare-handed the ball on the run, and attempted a rushed throw that again bounced on the turf and skipped wide to the second base side of first.

In the fifth, Donaldson knocked down a 107-mph Tyler Austin rocket and made his best throw of the game. It didn’t have much behind it, but also didn’t need to, as it tailed towards the feet of Justin Smoak at first for an out.

And in the sixth, Austin again chopped a grounder to third, this time a much more routine ball that Donaldson easily corralled with plenty of time to throw. He double-clutched as he repositioned the ball in his hand, and still skipped his throw off the infield dirt and wide to the second base side. Smoak was nearly pulled off the bag, but made a terrific stretch to snare the ball and ensure the out.

After the game, Donaldson said that final throw “came out of my hand funny.” And, to his credit, he got every out he reasonably could have, with the exception of the ball off Happ’s leg, which he had very little chance to convert considering how quickly Hicks sprinted up the line. In the end, dead arm or not, the plays were made.

“It is what it is. It feels good,” he said. “I didn’t really have to throw it too hard today. So, I didn’t.

But it certainly didn’t look good. And if the issue persists, the Blue Jays could be exposed to a situation in which teams bunt the ball towards Donaldson at third to test his arm. Gibbons said he would likely give Donaldson more games at designated hitter going forward, as the 32-year-old works to regain strength in his shoulder.

“Obviously, it was off today,” Gibbons said. “We don’t think it’s a big deal — it’s just dead. … I’m not particularly worried.”

The good news is Donaldson looked like himself in the batter’s box, taking the aggressive swings he often does. He put a 100-mph Luis Severino fastball in play at one point, and slid head-first with his arms extended out ahead of him when he stole second base without a throw after drawing a walk in the sixth.

“I felt good,” he said when asked if the lack of shoulder strength affected him at the plate. “I missed a few pitches today. But I felt like I had some really nice at-bats. … And, you know, it’s getting your sights back to real stadiums and things of that nature. It’s important.”

And it’s not like Blue Jays fans haven’t seen a prodigious hitter play a full season with a shoulder issue before.

Only 14 games into his 2015 season, Jose Bautista injured his right shoulder trying to nab Delmon Young at first base with an aggressive throw from the outfield. He missed five consecutive games before returning and serving exclusively as Toronto’s designated hitter for a little more than a month.

Bautista’s injury was more severe than the issue Donaldson says he’s experiencing. He described it at the time as “inflammation inside the shoulder joint, which caused an impingement,” and chronicled a nightly routine of ingesting powerful pain killers in order to fall sleep.

After his stint as a designated hitter, Bautista returned to duty in right field, but clearly wasn’t himself when throwing. He logged only four outfield assists over the remainder of the season, and sat out the All-Star Game he was selected to play in that July as he continued to rehab the ailment.

And there’s the thing. Despite the injury, Bautista was still an all-star, putting up a .913 OPS with 40 homers and contributing some of the most indelible moments in Blue Jays history that October, including the unforgettable bat flip and his oft-overlooked two home run performance in Game 6 of the ALCS.

For his part, Donaldson said his shoulder felt better as Thursday’s game went on. And while there is no tried and true timeline for overcoming a case of dead arm, it is an issue athletes can generally get past in the near-to-mid term with a program of physical therapy and strengthening.

Of course, the physical demand of playing baseball every day likely doesn’t help, which could explain why Donaldson got into only 13 games this spring, logging just 33 plate appearances. But the Blue Jays can alleviate that stress by playing Donaldson as a designated hitter, and don’t be surprised to see that happen in the coming days and weeks, particularly when Toronto plays a day game following a night game.

So, reason for concern? Sure. But reason for dread? Not quite. At least not yet.

“There are things that we’re going to be able to do to get it there,” Donaldson said. “I think I can make it work.”