NFL players and owners are at odds over surfaces their teams play on
49ers star never wants to play for team with artificial turf field
49ers' George Kittle, Nick Bosa join NFL Twitter in calling for safer fields – NBC Sports Bay Area & California
Takeover complete! 49ers group complete purchase of Leeds United with backing from US golf stars Rickie Fowler, Justin Thomas & Jordan Spieth
Few surprises among NFL's top teams so far this season
Artificial turf vs. real grass: NFL's ongoing problem with playing surfaces
Aaron Rodgers' injury prompts renewed call for NFL grass over turf from David Bakhtiari: 'You care more about soccer players'
Artificial Turf Track Installed at Levi's® Stadium
49ers' move to Santa Clara has been an absolute bust
NFL players and owners are at odds over surfaces their teams play on
Turf time: Ranking the best and worst fields in the NFL - Sports Illustrated
Sources: NFLPA backs 49ers' criticism of MetLife Stadium field, pushes for review of field turf