Bucky Irving fantasy football managers have spent most of the season patting themselves on the back after getting RB1-level production on the cheap. However, the other shoe (or in this case, walking boot) appears to be dropping. After one of the best games of his career, the running back finds himself dealing with an injury.However, how much should you worry about the running back? It turns out, quite a bit. Here's a look at the situation, starting with one beat reporter's observation. Posting on X on Oct. 1, reporter Greg Auman noted that it wasn't "looking good" for Irving."Not looking good for Bucs RB Bucky Irving, who had a boot on his left foot and was on crutches at today’s walkthrough," Auman posted. "Focus on Rachaad White and Sean Tucker for Sunday in Seattle."As such, managers should make the move to slide in a running back to replace Irving now, as it appears to be trending toward the back missing Week 5. Of course, the new question becomes how much time Baker Mayfield's running back could potentially miss.Bucky Irving fantasy outlook for rest of 2025 seasonBucky Irving at Philadelphia Eagles at Tampa Bay Buccaneers - Source: ImagnIf healthy, Bucky Irving leaves little reason to doubt his ability to remain a set-and-forget running back. Of course, it isn't that simple. The biggest factor is his health, which has become a bold question mark. In a pair of X posts made on Oct. 1, NFL insider Adam Schefter limited the scope of the alarming situation."Buccaneers do not fear Bucky Irving’s foot sprain is a long-term injury, per source. The team considers it a week-to-week injury."As such, managers can exhale a little bit. However, it still could be two or three games before he's back on the field, depending on how things go in his recovery. In the short term, managers should be ready to add the back to their IR and pick up a reliable name off the waiver wire if needed.Kansas City Chiefs running back Kareem Hunt might be the most reliable name available based on pure volume, with 13 carries in each of his last two games, including a touchdown.If Irving can get through his recovery without a hitch by the team's Oct. 20 showdown against the Detroit Lions, the running back still could hit 1,000 all-purpose yards with time to spare. If he can only miss a week and get back on the field in time to face the San Francisco 49ers on Oct. 12, it could be a relatively painless absence for managers if they can hit with a random one-week wonder.In short, Irving's injury isn't a disaster but merely a small setback after a productive opening month.