​Jan 5, 2025; Glendale, Arizona, USA; San Francisco 49ers defensive tackle Sam Okuayinonu (91) against the Arizona Cardinals at State Farm Stadium. Mandatory Credit: Mark J. Rebilas-Imagn Images | USA TODAY Sports via Reuters Con The San Francisco 49ers are preparing for their Week 1 contest against the Los Angeles Rams in Australia later this week, but they’ll be without one of their top rotational defensive linemen.Head coach Kyle Shanahan confirmed that defensive end Sam Okuayinonu broke his foot, calling it a “bad injury.” The team is hoping he can return later in the season, but the loss is a blow for the 49ers’ defensive line, which is already without Mykel Williams, who is starting the year on the Physically Unable to Perform (PUP) list.With Okuayinonu out, the 49ers signed defensive end Khalid Kareem to the practice squad over the weekend. He could see the field as early as Week 1. Currently, the Niners have Keion White, Nick Bosa, Romello Height, and Kareem as the healthy defensive ends on the roster, while Osa Odighizuwa, Alfred Collins, C.J. West, Gracen Halton, and James Thompson Jr. are the healthy interior defensive linemen.Okuayinonu did not travel with the 49ers and was placed on Injured Reserve over the weekend. We’ll see now if he can return before the end of the season. The 28-year-old defensive lineman has been one of the success stories for the 49ers over the past few years, being a versatile lineman who could slide inside on passing downs. He had 39 tackles, three sacks, and a forced fumble last year.According to Matt Barrows, the injury occurred when Okuayinonu, who previously had a plate in his foot, was stepped on in practice last week. He’ll now have to have surgery on his foot and will likely miss a significant portion of the 2026 season.