It may be the first game in October for the San Francisco 49ers on Sunday, but this Week 5 matchup with the Arizona Cardinals will feel anything other than fall. With a heatwave hitting the Santa Clara area, the Niners were hoping to make a last-minute modification to their uniforms for this matchup to better combat the weather. 

Head coach Kyle Shanahan told reporters Friday that the team put in a request to the NFL to switch from their usual red home jerseys to white, as that color would be less absorbent to the sun’s rays. However, the league declined. The Cardinals will wear their white jerseys on Sunday. 

“We asked on Monday, and we weren’t allowed to do it,” Shanahan said, via 49ers Webzone. “You had to [request] it before the season started. So in order for us to do it, we’ve kind of got to make like a conscious decision or a commitment before the year that we wear all whites until like the middle of October or whatever, and then go to normal. But it’s not usually this hot, so we’ll probably do that now just in case.”

It appears as if the team may elect to simply don its white jerseys for the start of the year going forward to avoid this type of situation in the future. While the league did veto the 49ers’ request to wear those white jerseys, they were able to switch to their throwback uniforms that feature the red jerseys but white pants in place of the gold. 

“Yeah, they’ll let us do our throwbacks, just alternate it with other ones, so we’ll get as much white on as possible,” Shanahan said. “And the most we possibly can do is white pants, so hopefully, it helps a little.”

Currently, there is an excessive heat warning around Levi’s Stadium that will be in effect until Saturday at 11 p.m. PT, according to the National Weather Service.