SEATTLE -- The Mariners became the first team in Major League Baseball to make COVID-19 vaccines available to fans attending games at T-Mobile Park, a plan that was put together in less than one week via a partnership with the city of Seattle and Sounders FC, which began executing a similar process at its match on Sunday.

The plan is for this to be an ongoing availability at Mariners home games until further notice, and it began with Tuesday’s 7:10 p.m. PT contest against the Orioles, when they administered 160 shots over the nine-inning contest.

No appointment is needed. Vaccines will be offered on a walk-up basis at three locations inside T-Mobile Park:

• Edgar’s Home Run Porch, near the left-field foul pole
• Near section 105
• Rooftop Boardwalk on the View level (300 level)

Vaccinations will be administered by Seattle Fire Department EMS personnel, and Virginia Mason Franciscan Health will have staff and volunteers on hand to support the process. Vaccines are free of charge and will be available upon gates opening two hours prior to first pitch. Only those fans 18 and older who have not already received their first dose are eligible.

Fans who are eligible to receive the vaccine will have the choice of a single-dose Johnson & Johnson shot or the first dose of the Moderna vaccine. Those receiving the Moderna shot will be able to schedule their second dose at one of the city of Seattle’s community vaccination sites at the Lumen Field Event Center, Rainier Beach or West Seattle. Because the Pfizer vaccines are more challenging to transfer due to their requirement to be stored at such cold temperatures, those aren’t being offered at this time. But that could change.

The Seattle Fire Department said that each station is capable of administering 50 shots per hour and that it can oversee roughly 500-600 per game.

So, how did such a robust, calculated and game-changing plan all come together?

It began last Tuesday when Stanton’s office reached out to Seattle mayor Jenny Durkan asking how the Mariners -- who’ve already been among the most aggressive in vaccine education and awareness in all of baseball -- could help the governing and medical bodies further.

“If you come here and you have been vaccinated, stay tuned for some special announcements we'll be making in the next 48 hours with respect to incentives to get vaccinated and come to see a game,” Stanton said.

The vaccine supply in Washington state, which had a slower rollout than other states, has now reached more supply than demand, which allowed for the Mariners and Sounders to join the distribution efforts.

As of Tuesday, 70 percent of Seattle’s population ages 16 and older -- those eligible to receive the vaccine -- have at least the first dose of the two-dose vaccines Moderna or Pfizer or the single-dose Johnson & Johnson, according to Durkan.

“It's a remarkable threshold that we've reached,” Durkan said. “And it shows how much people care about each other and their family. And it shows that we as a city, throughout this pandemic have stood up to do the right thing for ourselves, for our neighbors for our community. And we're here today because our teams have done that to showing the way.”

In related vaccination news, the Mariners could be expanding capacity for home games soon. Washington Gov. Jay Inslee announced on Monday updated COVID-19 guidance orders that will allow outdoor venues to add vaccinated sections and increase their capacity to 50 percent or up to 22,000 people (whichever is lower). However, the number of unvaccinated people who can attend will still be capped at 9,000.

The guidelines would allow for vaccinated sections to operate at full capacity without six feet of physical distance. Triple-A Tacoma announced that it will be operating at 50 percent capacity thanks to the new guidance for its season opener on Thursday.

For those unable to receive a vaccine at a Mariners game, the Lumen Field Event Center location across the street from T-Mobile Park is administering no-appointment vaccinations on Wednesdays and Saturdays. For information about other vaccine locations, or to schedule an appointment, visit Seattle.gov's vaccination page.

Virginia Mason Franciscan Health has administered more than 300,000 vaccines to date across the health system. Community members are also welcome to visit the health system’s website to sign up for vaccination appointments.