Ibrahimovic, 39, scored his 14th goal in the league this season in just his 11th appearance as Milan thumped Crotone 4-0 as the Rossoneri maintained their two-point lead over Internazionale at the summit.
"It's difficult to be surprised by Ibrahimovic," head coach Stefano Pioli said after the game as they chase their first league title in a decade, as per FirstPost.
Sweden's all-time record scorer reached the historic landmark on the half-hour when he opened the scoring, taking his overall club tally to 500 with nine different clubs over an iconic career.
In the second half, he made it 501 goals while Ante Rebic netted the other two in the impressive display at the San Siro.
"To hold up at this level means you're an exceptional professional and he's helped by a physique that few have," continued Pioli.
"He's a champion, an athlete who has great motivation, he takes care of his body scrupulously. Sometimes he's tired, but he never fails."
Having made his first-team debut for Malmo in 1999, the Swede played down the occasion after the game in his 825th game over an incredible 22-year career thus far.
"It means that I have scored a few goals in my career," said the Swede, who was substituted off with 15 minutes to go.
"The important thing is to continue to help the team in the best possible way. My job is to score and create situations to score."