CREATE TABLE table_2402864_1 (year NUMBER, regular_season VARCHAR2, league VARCHAR2)

What was the earliest year where USL PDL played in 3rd, Southeast season?
SELECT MIN(year) FROM table_2402864_1 WHERE regular_season = "3rd, Southeast" AND league = "USL PDL"
SELECT MIN("year") FROM "table_2402864_1" WHERE "3rd, Southeast" = "regular_season" AND "USL PDL" = "league"