Look away, fantasy football managers. Look away, San Francisco 49ers fans. We have an update on Christian McCaffrey’s Achilles injury, and it’s not looking great. 49ers head coach Kyle Shanahan told the media on Friday that the club will not be opening the practice window for McCaffrey, who has been on injured reserve since the start of the season with Achilles tendonitis. ESPN’s Adam Schefter reported that McCaffrey is unlikely to face the Kansas City Chiefs next week in the much-anticipated Super Bowl rematch. The 49ers will have 10 days off before their matchup with the Chiefs. On Thursday night, the 49ers beat the Seattle Seahawks. They don’t play again until October 20. But McCaffrey won’t be practicing, and Shanahan will have to continue to embrace life without him. Replacement running back Jordan Mason, who has masterfully filled McCaffrey’s large shoes, exited Thursday night’s game with a shoulder injury. The third string back, Isaac Guerendo, rushed for 99 yards on 10 attempts during the victory against Seattle. The fourth-rounder out of Wisconsin, who most people didn’t even know existed until Thursday, looked up to the task to replace McCaffrey and Mason. Mason is believed to have a sprained AC joint that isn’t considered serious, according to ESPN, but will undergo further testing on Friday to confirm the injury. McCaffrey traveled to Germany to see an Achilles specialist in the last week of September. It’s an injury that has bothered him since the start of training camp and has now interfered with his ability to suit up and play for the Niners on Sundays. “I know he’s going to see a specialist that I believe can help him with his Achilles process,” Shanahan said in September. “I think he’s doing that over these next few days, and hopefully it’ll help.” NFL Network’s Ian Rapoport reported that McCaffrey received treatment similar to a platelet-rich plasma (PRP) injection. Could you imagine flying 11 hours from the Bay Area to Germany just to go see a doctor? Well, that’s what McCaffrey did, and he’s still not back on the field. New reports indicate that McCaffrey could return to action in the beginning of November. After the Chiefs, the 49ers will host the Dallas Cowboys for Sunday Night Football on October 27. They’ll have a bye week after that game and will return to action on November 10 against the Tampa Bay Buccaneers. Perhaps that’s the date to circle for McCaffrey’s return. For now, 49ers fans and fantasy football managers will have to wait, read injury reports, and watch Mason and Guerendo handle business in San Francisco.