By CBS3 Staff

PHILADELPHIA (CBS) — On this very hot Thursday, fans in South Philadelphia will have to wear masks when indoors at Citizens Bank Park and Lincoln Financial Field. Philadelphia issued a new mask requirement that includes masks while indoors at all locations unless proof of vaccination is required.

Fans at the Phillies and Eagles games on Thursday wore wear masks while in elevators, restrooms, and the team stores.

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It’s a scorcher across the region Thursday and Phillies fans were trying to keep cool and hydrated as they hope for a win to avoid being swept by the Los Angeles Dodgers.

“I dressed appropriately,” Jennifer Lucano, of Cinnaminson, said. “I’m drinking plenty of water in between some of the other beverages. That is my plan.”

CBS3 spoke with a group of Phillies fans tailgating about how they’re going to handle the hottest day of the year thus far.

“I’m very comfortable,” Tyron Steele, of Sicklerville, said. “I’m gonna relax with my light colors on and go Phillies.”

“I bought seats in the shade and I’ve been planning to come here for two months,” Andrew White said.

The Eagles opened the 2021 preseason Thursday night against the Pittsburgh Steelers at Lincoln Financial Field.

Fans attending the game are allowed to bring one sealed water bottle into the stadium with them. Fans didn’t let the latest mandate impact their excitement.

“We’ve been coming to the same lot, D6, for 15 years,” Tom Lacroix of Southampton told CBS3. “We’re all family, we all know each other.”

The Phillies and Eagles updated their health and safety guidelines on Wednesday after the city announced a new mask requirement while indoor at businesses. The only exception to the mask mandate is if a business requires all employees and guests to show their vaccination cards.

The reaction to the mask requirement is mixed, with some not surprised at the development.

Fan Matt Ciciarelli said, “I heard about it yesterday when they made the announcement, and you could kind of see it coming.”

While fans will not have to show proof of vaccination at the Linc, so they will be required to wear a mask while at indoor locations. Unvaccinated fans are strongly encouraged to always wear a mask unless eating or drinking. Fans should also bring their own masks with them to the stadium.

CBS3’s Matt Petrillo and Alicia Roberts contributed to this report.