The phrase "indifferent form" means that someone or something doesn't care or show any particular preference. It implies a lack of interest or concern. Full definition
It's a four game run of indifferent form for God's sake. (kopleft.com)
Neil McCarthy's Finnegan, who showed flashes of both brilliant and indifferent form at Santa Anita this winter, was hard - put to win the California Derby at Tanforan on Saturday — passing the wire barely a head in front of E. O. Stice's Monk's Hood and two heads in front of Royal Orbit, who races for Mrs. J. Braunstein. (si.com)
Arsenal and our local rivals Tottenham went into this north London derby in pretty indifferent form but knowing that a win could and would kick start the campaign. (justarsenal.com)