CREATE TABLE table_204_363 (id DECIMAL, "res." TEXT, "record" TEXT, "opponent" TEXT, "method" TEXT, "event" TEXT, "date" TEXT, "round" DECIMAL, "time" TEXT, "location" TEXT, "notes" TEXT)

to whom did brock lesnar lose his first fight ?
SELECT "opponent" FROM table_204_363 WHERE "res." = 'loss' ORDER BY "date" LIMIT 1
SELECT "opponent" FROM "table_204_363" WHERE "res." = 'loss' ORDER BY "date" NULLS FIRST LIMIT 1