Barcelona delivered a flawless home finale, beating Real Betis 3-1 at Camp Nou on Sunday to finish with a perfect 19 wins from 19 La Liga matches at home this season.
The club had announced on Saturday that 37-year-old Robert Lewandowski would depart after four seasons with the Catalan giants.
Goals: Brazilian winger Raphinha scored twice, with defender João Cancelo adding the third goal in the victory over Real Betis.
Barcelona had already clinched its second consecutive league title two rounds before the final home match.
"It has been an honor to play for this club," Lewandowski said. "We've enjoyed some great moments in these four years. I am very proud of everything we have achieved together. Today I say goodbye, but I will always carry Barcelona in my heart."
After the final whistle, Lewandowski's teammates lifted him into the air in celebration and lined up to applaud him as he walked toward the locker room.
Lewandowski's Barcelona legacy: Three La Liga titles in four seasons, one Copa del Rey, and 119 goals in 192 appearances across all competitions.
"Thank you so much, fans," he added. "Once a Barça fan, always a Barça fan."