Who was American art critic and collector who endorsed abstract expressionism?

The American art critic and collector who endorsed abstract expressionism was Clement Greenberg. He played a pivotal role in promoting the movement during the mid-20th century, particularly advocating for artists like Jackson Pollock and Mark Rothko. Greenberg's critical essays emphasized the importance of formal qualities in art, significantly influencing the direction of modern art and the perception of abstract expressionism. His writings helped to establish the movement as a dominant force in American art.