Nick Diaz's identity as a martial artist is inseparable from his training under Cesar Gracie, one of the most respected figures in Brazilian Jiu-Jitsu. Earning his BJJ black belt under Gracie's guidance, Diaz developed within a lineage known for producing technically complete, well-rounded fighters. The Cesar Gracie Jiu-Jitsu environment forged him alongside teammates including his brother Nate Diaz and Gilbert Melendez — a tight-knit competitive unit that carried the Gracie Jiu-Jitsu philosophy into the highest levels of professional combat sports.

The principles instilled at Cesar Gracie Jiu-Jitsu are evident throughout every dimension of Diaz's game. His style centers on active guard work, persistent submission hunting, and the seamless integration of grappling with high-volume boxing output — a hallmark of the Cesar Gracie school. Rather than operating along a single axis, Diaz built a game in which striking threats and submission attempts reinforce each other, forcing opponents to navigate danger on multiple fronts simultaneously.

Nick Diaz established himself as one of the premier welterweights of his era during his reign as Strikeforce Welterweight Champion. After capturing the title, he defended it multiple times, cementing his standing as one of the organization's most dominant champions during Strikeforce's peak years.

Among his most defining defenses was his third title defense against Paul Daley, a striker renowned for his knockout power. Rather than retreat from Daley's pressure, Diaz absorbed it, imposed his grappling-based game plan, and ultimately secured a successful defense. The bout illustrated his capacity to neutralize elite striking threats while maintaining his own submission finishing ability — a complete performance that stands as one of the signature moments of his Strikeforce tenure.

Nick Diaz was officially booked to face Vicente Luque at UFC 310 on December 7, 2024, marking a confirmed return to the Octagon for the longtime fan favorite. The matchup generated significant anticipation before Diaz withdrew from the event, ending the bout before competition could begin.

In January 2025, Diaz entered a rehabilitation facility, redirecting his focus toward personal health and recovery. His coach Jose Garcia described his progress in encouraging terms, noting that Diaz was doing "exceptionally well." The withdrawal from UFC 310 and the subsequent period of rehabilitation reflect a phase in Diaz's life defined by health prioritization, with those close to him expressing optimism about his trajectory.