In a satisfying case of delayed gratification, I heard drummer Evan Verploegh and saxophonist Ben Baker perform on the porch of a stately home last week. Released ten months ago, the duo’s Singles was one of the best albums released by Kansas City musicians in 2021. Yet I only managed to catch up with the tandem performing without other accompanists on Sunday, August 7. In spite of the suffocating heat, the urgent rush of free improvisation resembled a perilous downhill slalom. The athletic endeavor lasting about 50 minutes attracted more than a dozen intrepid friends, fans and curious passerby.