The 40-year-old midfielder, who started the game under manager Fabian Hurzeler, surpassed Gareth Barry's previous record of 653 appearances.
The milestone came as Brighton ended a six-game winless streak, with first-half goals from Diego Gomez and Danny Welbeck securing a comfortable victory. The win lifted the Seagulls two places to 12th in the table, while Brentford, seventh, saw their European hopes dented.
Milner, who began his career as a 16-year-old at Leeds United in 2002, has also played for Newcastle United, Aston Villa, Manchester City, and Liverpool. Over his career, he has scored 56 Premier League goals and provided 90 assists, including a career-high 12 assists in the 2009-10 season with Villa.
Reflecting on his record, Milner credited his longevity to "drive and hunger," as well as a commitment to contributing to younger teammates. "I want to push them and help them get to the highest level as quickly as possible," he said. "I feel like I can still contribute minutes. Hopefully, I've proved the last few games that I can still help on the pitch."
Hurzeler praised Milner as a "role model on and off the pitch," highlighting his professionalism and leadership. "Every week and in every training session he runs the most, he sprints the most. He is capable of doing a lot of impossible things," the Brighton manager said.
Milner's achievement has drawn accolades from former teammates and rivals alike. Wayne Rooney, who played 37 times for England alongside him, said: "Milly deserves to break the record. It's an incredible achievement and shows that when you work hard, it pays off."
After the final whistle, Milner celebrated with teammates and the away fans, but remained focused on Brighton's season. "It's a big number and it's nice to get to the record, but for me it's always been about the team. I'm desperate to do well for Brighton and finish the season strongly," he added.
With 11 Premier League games remaining, Milner has the opportunity to extend his record further, setting a benchmark that may stand for years to come.
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