Music competitions, for all their negative qualities, can launch extraordinary careers. Yekwon Sunwoo is one example, remembered in Washington for his first prize at the final William Kapell International Piano Competition in 2012. On the heels of winning the Van Cliburn International Piano Competition last year, the Korean pianist played an outstanding recital Wednesday at the Kennedy Center Terrace Theater, presented by Washington Performing Arts.

Nothing about Sunwoo’s program smacked of the showpiece territory exemplified by music competitions. The opening work, Percy Grainger’s “Ramble on the Last Love Duet From ‘Der Rosenkavalier,’ ” was delightfully weird, humid with triple nostalgia — of Strauss for a lost Vienna, of Grainger for his friendship with Strauss and for his recently deceased mother. Sunwoo gave the piece orchestral scope, not necessarily in volume, but in variety of color, using all three pedals to create sculpted sound worlds that caught the opera’s vast but intimate scale.

Further highlights of delicacy and elegance abounded in Schubert’s Four Impromptus, D. 935. Well-applied rubato, both speeding up and slowing down, gave each piece a different romantic sheen, mercurial in No. 1, pallid in No. 2. Each variation in No. 3 had a character defined by degrees of touch at the keyboard, especially the turbulent minor variation and the gossamer right hand of the final one. The more daunting challenges of the last Impromptu all came together with exquisite refinement, including parallel thirds, double-hand scales and trills.

Sunwoo had the least success with the Brahms Piano Sonata No. 3, more the fault of this rambling, overlong work than the performance. The pianist tempered the work’s loud excesses most convincingly, pointing and voicing full-textured chords in both hands to yield a full palette of dynamics even at the loud end.

The first encore continued in this unexpected vein, with the Albumblatt in A Minor, a piece written by Brahms in a friend’s music notebook and rediscovered only in the past decade. Only the second encore, a staggering rendition of Liszt’s fiendish “La Campanella,” served as a reminder of Sunwoo’s competition successes.