SEATTLE -- The Mariners’ group of elite prospects at Summer Camp has grown by one, as 19-year-old outfielder Julio Rodriguez joined the team for his first formal workout on Friday after missing the initial five days of camp.

Rodriguez is Seattle’s No. 2 prospect and No. 18 overall in baseball, per MLB Pipeline, and he joins fellow outfielder Jarred Kelenic (No. 11 overall), right-hander Logan Gilbert (No. 38), first baseman Evan White (No. 56) and right-hander George Kirby (No. 100) among the Mariners’ highly regarded young group that is part of the club’s 60-player pool.

Rodriguez is the second youngest player in Seattle’s camp, behind only 18-year-old shortstop Noelvi Marte, the club’s No. 6 prospect.

• Marte a big league presence at camp

The Mariners haven’t specified why Rodriguez wasn’t in attendance earlier, but he was one of six players who didn’t take part in the initial workouts and wasn’t seen at camp until Thursday when he briefly played catch in the outfield with Kelenic.

Per MLB policy, the Mariners have only announced that three people tested positive on their initial COVID-19 tests prior to camp.

Major League Baseball has instituted a COVID-19 list this season, although clubs will not announce which players are placed on it due to privacy laws regarding individuals’ health. Players may address their status if they wish, though they are not required to do so. Merely being placed on an injured list without further explanation is not confirmation that a player has tested positive for COVID-19. For example, potential exposure to a person who has the virus can be sufficient cause.

The Mariners are beginning intrasquad games on Friday afternoon and will play every day leading up to their July 24 regular-season opener in Houston, but pitchers and some of the young position players who aren’t competing in that day’s scrimmage will instead work out in the morning. Rodriguez will be part of that group at least through the weekend.

“We'll get him up to speed,” Mariners manager Scott Servais said Friday morning. “We’re excited to have him on the field. We’re looking forward to that. Everybody knows the energy he brings, and he and Noelvi Marte are the best of friends, so they’ll both have big smiles on their faces as they go through the workouts and get going in the games here, that’s for sure.

“Julio is healthy and feels greats. He’s anxious to get out there, but you won’t see him in a game probably for the first 3-4 days.”

Rodriguez hit .326/.390/.540 with 12 homers and 69 RBIs in 84 games for Class-A West Virginia and Class A Advanced Modesto in 2019, his first full season of pro ball. He was invited to the Mariners’ Major League camp this spring in Arizona, but he went just 2-for-13 with six strikeouts in nine Cactus League games and had been sent down to Minor League camp before the season was shut down on March 12.

• Rodriguez eager to make his mark with Mariners

He should get plenty of playing time in the intrasquad games once he’s ready, as the Mariners only have five other full-time outfielders in camp so far.

Haniger remains on hold

Servais reiterated that right fielder Mitch Haniger is limited to physical therapy and rehab work at this point while on the 45-day injured list as he continues recovering from surgery on a herniated disc. Haniger is not part of the 60-player pool, so he can’t be with the team at T-Mobile Park.

“I don't know the timeline on actually getting into baseball activity, maybe later on in the summer we’re hopeful he can start picking up some of that,” Servais said. “The reports are good. I'm anxious to get Mitch back, but again, no timeline, not rushing anything. We want to make sure he's 100% and his strength is back and everything is working fine before he gets into any baseball activity.”

Keeping close to home

While most MLB teams will play up to three exhibition games against other teams prior to the regular season, the Mariners are sticking strictly to intrasquad competitions prior to Opening Day because there are no nearby teams to play against in Seattle.

“In an ideal world, if we could drive down the street and play another team, that would be awesome,” Servais said. “But whether it was going to Houston a couple days early to play a couple exhibition games against them or going somewhere else before we went to Houston, it didn't make a whole lot of sense to me or [Mariners general manager] Jerry [Dipoto] when we talked about it.

“I think we're doing the right thing. The goal here is to stay healthy and stay safe and get to the season. I think that's something that could kind of derail that. So I'm not that worried about it. I think we will create a competitive environment here, hopefully keep our guys healthy and ready to go when the bell rings.”

Short hops from T-Mobile Park

• Servais said that right-hander Kendall Graveman looked very good while facing live hitters in batting practice for the first time on Thursday. Graveman, returning from a nearly two-year absence following Tommy John surgery, was hitting 94-96 mph with his fastball.