The claim is true because multiple reports published in late July and early August 2026 state that Conor McGregor underwent surgery to repair a torn ACL in his right knee.
Conor McGregor underwent ACL surgery.

Conor McGregor provides update after surgery on injured knee
Source: mmajunkie.usatoday.com
Key Evidence
MMA Junkie reported that McGregor underwent surgery for an injured ACL and meniscus in his right knee.
TMZ, Sherdog, Fox News, Bleacher Report, and other outlets independently reported that he had surgery to repair a torn ACL, with several describing it as successful.
The reports were published or updated approximately one to two weeks before August 15, 2026.
What the Evidence Shows
Available reporting consistently supports the statement. MMA Junkie reported on August 5, 2026, that McGregor had undergone surgery for an injured ACL and meniscus in his right knee. TMZ, Sherdog, Bleacher Report, Fox News, and other outlets likewise reported that he had surgery after sustaining the injury during his fight with Max Holloway at UFC 329.
The sources differ slightly in wording and additional details. Some describe the procedure as ACL surgery, while others refer more broadly to surgery for ACL and meniscus injuries. Several reports say McGregor characterized the operation as successful or said it went well. Those details do not conflict with the core claim that the surgery occurred.
The evidence is primarily based on McGregor's own public update, as relayed by multiple sports and entertainment publications. The provided sources do not include an independent medical record or statement from the surgical team, so the exact procedure and medical outcome cannot be verified beyond those reports.