The official Pulitzer website isn't working right for me, but Wikipedia has Joe Turner's Come and Gone listed as the Pulitzer finalist that lost to The Heidi Chronicles. It only has The Piano Lesson listed during its winning year.
August Wilson had quite an impressive Pulitzer track record. He had 6 Pulitzer finalists in 14 years, with two winners. He is the most-nominated playwright in Pulitzer history. (There is an asterisk in that the Pulitzer non-winning finalists were only publicly announced starting in 1983.)