SEATTLE -- For the first time since Spring Training came to a screeching halt on March 13, Mariners players reported for work on Wednesday. But much has changed.

For starters, the players checked in at T-Mobile Park in Seattle instead of the Peoria Sports Complex in Arizona, with the resumption of camp having moved 1,100 miles north to the club’s regular-season stadium instead of dealing with the 102-degree heat on the practice fields of Peoria.

But it’s more than just location that has shifted in the ensuing 3 1/2 months. Instead of strolling into a carefree clubhouse and roaming freely about the facility, players and coaches now enter a controlled environment that is carefully regulated for safety concerns to allow for Major League Baseball’s return during the COVID-19 pandemic.

MLB put together a 101-page “operations manual” that outlines how players will be kept safe and how teams must strictly control who gets near players and staff in order to limit any potential spread of the coronavirus.

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While Summer Camp officially opened Wednesday in preparation for season openers on July 23-24, players first had to take COVID-19 tests and will have to test negative before taking the field as a group for the first time on Friday.

And that group will actually be a series of smaller gatherings, with the 60 invited Mariners players broken into morning and afternoon shifts and further divided into smaller sets where possible.

“It’s our intent to break down into groups of 8, 10, 12 for the purposes of workouts,” general manager Jerry Dipoto said. “And where we can break into smaller groups than that, we will. For instance, pitchers who might need to throw sides and get gym work in, we might work in a group of four with them. We’re going to individualize it as much as we can.

“And using T-Mobile, we're also planning on spreading out. So we’ll use both the home and visitors clubhouses, as well as an auxiliary space.”

The days of manager Scott Servais calling all the players together in the clubhouse every morning for a team meeting are gone. Instead, smaller groups will gather in the stands -- where they can be properly spaced out -- or other indoor meeting rooms like the Ellis Pavilion.

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The players clubhouse area has undergone a makeover of its own. Instead of a large room with huge TVs, couches and a pool table in the middle ringed by players’ lockers on the outside, the TVs, couches and pool table are now gone so that portable lockers fill the middle space and players aren’t all sitting side-by-side.

Social distancing is the new norm and, yes, players are required to wear masks except when they’re on the field or working out in ways where the face covering is prohibitive.

Loitering in the clubhouse is also frowned upon. And sitting down to eat together? Forget about it. Instead of a breakfast buffet in camp or postgame spread once the season begins, players will be handed prepackaged meals on their way out the door.

“It’ll be kind of a grab-and-go station,” Dipoto said. “There won’t be a postgame meal, sit down and gather with your teammates. It’s more of a pick up the box on the way out so that we are not promoting gathering. There’ll be restricted times for who’s there during the course of Spring Training 2.0. We’ll have a pretty rigid schedule on when players report and when they move on.”

Mariners office staff is also being limited as much as possible, with those who can work from home continuing to do so. Media will be allowed to watch the workouts and attend games, but that group will be limited to 35 per day, including broadcasters, photographers, writers and production staff.

Everyone who enters the stadium -- including players -- must first pass through a testing area each day and answer a series of health questions and have their temperature checked. Only players, coaches and limited support personnel -- labeled as the Tier 1 and 2 groups -- are allowed on the field level. Media and others -- labeled as Tier 3 -- have to enter on the club level and will be confined to specific work areas.

Photographers will be allowed in certain areas of the lower bowl, but can’t get closer than three rows of the playing field and will be restricted in their movements as well.

Player interviews with the media will be conducted only via Zoom or phone calls, with no personal contact allowed.

After players leave the park, media departs the press box and staffers head for home, there’ll be a thorough daily cleaning of all areas using electrostatic sprayers and UV-C light specifically designed to target COVID-19.

None of this even gets into the strict guidelines players must follow when they’re on the field once games begin, or on airplanes and buses when they start traveling.

For now, it’ll just be one step at a time as camp gets underway, socially distanced and properly masked.