Report: 49ers frustrated by Super Bowl practice field

Several members of the San Francisco 49ers are displeased with the team's practice field conditions in Las Vegas ahead of Super Bowl LVIII, sources told ESPN's Adam Schefter.

The 49ers are using the practice facility at UNLV before they take on the Kansas City Chiefs on Sunday. The NFL put in a sod field on top of field turf and started laying it last week, according to Schefter.

The NFL hardness score for fields averages 78, with no field being less than 70. But the 49ers' field in Las Vegas is reportedly considered in the 50s.

San Francisco head coach Kyle Shanahan said Monday that his team won't change "anything" regarding its preparation for the big game, according to Omar Ruiz of NFL Network.

"It improves each day, so hopefully it will get better and better," Shanahan added, per Cam Inman of The Mercury News.

NFL commissioner Roger Goodell also addressed the situation Monday.

"Work has been done every single day," Goodell said, according to Mick Akers of the Las Vegas Review-Journal. "We've had 23 experts out there, we've had the union out there, all of them think that's a very playable surface. It's softer than what they practice on, but that happens. ... All of our experts, as well as neutral field inspectors, have all said unanimously that it's a playable field."

The NFL ordinarily requires Super Bowl practice fields to meet specific standards by December. The league, however, has approved each Super Bowl practice facility after inspecting its playing surfaces along with the NFL Players Association.

The Chiefs, who are considered the home team in the Super Bowl this year, are practicing this week at the Las Vegas Raiders' training facility.

The 49ers are holding their first walk-through practice on the field Monday.