Player-boss Allan Johnston was sent off for Queen of the South as the promotion favourites failed to win for the first time this season, held to a 0-0 draw at East Fife.
The Doonhammers had won all four of their matches so far this term, and were inches away from going ahead just before half-time when Nicky Clark saw his close-range header tipped round the post by Michael Brown.
Johnston's team piled on the pressure early in the second half, Brown again forced into a great save to keep out Derek Lyle's long-range effort in the 51st minute.
Gordon Durie's side went close after 72 minutes when David Muir let fly from distance only to see his effort sail over the bar.
Johnston received his second yellow card of the game two minutes from time for a foul on Darren Smith.