Yusniel Díaz knows the only thing that keeps him from fulfilling his enormous potential and reaching the big leagues.

“Being healthy,” he simply stated before a recent Mesa Solar Sox game in the Arizona Fall League.

That’s been easier said than done for the Orioles’ No. 12 prospect, who hasn’t played in over 100 games in a season since 2017, when he was in the Dodgers system. He went to the AFL after that season, hitting .303 in 17 games for Glendale.

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A whole lot has happened since then. Díaz was hitting well in Double-A when he went to the Futures Game and belted a pair of home runs. A few days later, he was the top prospect sent to the Orioles in the Manny Machado blockbuster trade in July 2018.

It’s been slow going for Díaz in the Orioles system, mainly due to injuries. He managed just 76 games due to hamstring and quad issues in 2019, his first full season in the organization, though he did slug .472. A solid showing at the Orioles’ alternate site in 2020 led to a spot on the 40-man roster and hope that Díaz could ascend to Baltimore during the 2021 season.

Instead, he dealt with more quad trouble and a toe injury that limited him to 65 games.

“I feel kind of weird,” said Díaz, who just turned 25 this month. “I know I’ve worked really hard to be healthy on the field and to try and help my team win. It’s been really frustrating. I just want to keep getting better and get healthy.”

Playing in the AFL will help him make up for some of that lost time, and he went 4-for-18 over his first five games, with three of those hits going for extra bases. He’s always had a solid approach at the plate and that’s continued, with more walks than strikeouts in the early going for Mesa.

“It’s an opportunity to redeem myself and be the guy I’ve been the last two or three years,” Díaz said. “This year, I know I didn’t have a good year, so I want to focus on improving at the plate and to keep getting better.”

The time spent in Triple-A has helped inform him what he needs to do to find success at the highest level once that call finally comes.

“I know it’s not my best year, but it’s the same baseball,” Díaz said about the difference between the levels. “There are a lot of really good pitchers up there, almost in the big leagues or who have already played in the big leagues. I just want to adjust my timing at the plate.”

Orioles hitters in the AFL

Kyle Stowers, OF (No. 11): Stowers came to Arizona to put the finishing touches on a breakout season in which he played across three levels of the Minor Leagues, finishing with 27 homers and an OPS of .897. After three games in the AFL, the decision was made to shut Stowers down, giving him 127 games total played for the year.

Greg Cullen, 2B: Cullen came to the Orioles in November 2020 as a player to be named later in the late August Tommy Milone trade, but he only got into 38 games during his first year with his new organization. When he was healthy, he continued to be an on-base machine, drawing more walks than strikeouts to lift his career on-base percentage mark up to .393. Making up for some of those lost at-bats now, he got off to a 2-for-11 start with Mesa.

Ramon Rodriguez, C: A Minor League free-agent signing in March, Rodriguez was originally a late-round pick of the Dodgers, who released him in July 2020. He played somewhat sparingly in 2021, but did so across three levels, making a strong impression behind the plate. The Orioles sent him to Arizona to get him more at-bats (He had just 190 during the regular season) and see whether they have more than they anticipated when signing him.

Orioles pitchers in the AFL

Cameron Bishop, LHP: A 6-foot-4 lefty initially taken in 2017 out of UC Irvine, Bishop had been a starter over his first two full seasons of pro ball. He’s gotten more relief work in 2021, though like many of the O’s pitchers on this list, he missed a chunk of the season with injury. He’s getting some lost innings this fall while working to refine the command of his 90- to 94-mph fastball and a curve that flashes plus in a bullpen role.

Logan Gillaspie, RHP: Gillaspie has had a long and winding road to the AFL. He was pitching in independent ball for parts of two seasons before the Brewers signed him. He spent a year with them before getting released in September 2019. He found a new home with the Orioles in June 2021 and pitched his way to Double-A. Baltimore likes his stuff and wanted to give him more work in order to see more of him. Gillaspie struck out five over 2 1/3 hitless innings in his first fall outing.

Conner Loeprich, RHP: The Pirates took Loeprich in the 20th round of the 2018 Draft and dealt him to the Orioles in September 2020 for international bonus slots. His first full season with the O’s was interrupted by injury and he amassed just 56 innings. He has average stuff across the board with a fastball in the low 90s, and the Fall League gives him the time to show off his stuff to all 30 teams in his first Rule 5 offseason.

Nick Vespi, LHP: A lefty reliever taken out of the junior college ranks back in 2015, Vespi dominated in his first trip to Double-A to start the 2021 season and was a little less effective in Triple-A. He missed bats at both levels (11.9 per nine) but also walked 4.0 per nine. Working on his command and auditioning for a 40-man roster spot, he did strike out six over his first four AFL innings, but he also walked three.