Key keywords: Joey Bosa, San Francisco 49ers, 2024 NFL Free Agency, defensive end contract, NFL salary cap, Bosa brothers pass rush tandem, NFL free agent stalemate, 49ers Super Bowl roster construction Three-time Pro Bowl edge rusher Joey Bosa and the San Francisco 49ers have hit a significant impasse in negotiations for a potential free agent deal, per multiple league sources familiar with the talks, derailing widespread expectations that the star defender would join his younger brother Nick Bosa to form one of the most fearsome pass rushing duos in NFL history. Bosa, released by the Los Angeles Chargers in mid-March to avoid paying $135 million in remaining guaranteed salary on his previous five-year extension, entered free agency as the most coveted defensive player available this cycle, with 68 career sacks, 110 tackles for loss and a first-team All-Pro selection on his resume. The 49ers emerged as the clear front-runner for Bosa’s services within 48 hours of his release, with both Bosa brothers publicly expressing enthusiasm about the possibility of playing together for the first time since their college tenure at Ohio State. San Francisco’s front office identified edge rush depth as its top off-season priority after the team’s Super Bowl LVIII loss to the Kansas City Chiefs, where a lack of consistent pressure on Patrick Mahomes allowed the Chiefs to erase a 10-point second-half deficit. However, core disagreements over contract structure and guaranteed money have halted talks entirely as of late April. The 49ers, who are operating with just $11.8 million in remaining 2024 salary cap space after signing quarterback Brock Purdy to a record-breaking five-year, $210 million extension earlier this month, have offered Bosa a one-year deal worth $8.5 million in base salary, with an additional $4.5 million available via playtime and performance incentives. Bosa’s representation, by contrast, is seeking a two-year, $28 million contract with $22 million in fully guaranteed pay, plus a no-trade clause and a player option for the 2025 season. League insiders note that Bosa has drawn competing offers from the Buffalo Bills and Dallas Cowboys, both of which have enough available cap space to meet his contractual demands. The 49ers have stated they will not rework their offer unless they create additional cap space via contract restructurings of existing core players, or if Bosa lowers his asking price ahead of the 2024 NFL Draft at the end of the month. If no deal is reached before the draft, the 49ers are expected to use their first-round pick on an edge rush prospect, eliminating the remaining cap space earmarked for Bosa.