Stocks tumbled after St. Louis Fed president James Bullard said the first rate hike could come as early as Q1 2015, but fought back to finish nearly at break-even; Bullard, a non-voting FOMC member, has offered a similar take in the past.
Traders said the early selloff may have been the result of one or more large institutional investors pulling out some money as a portfolio allocation shift ahead of the quarter's end, rather than a response to any particular news.
Financials were among the hardest-hit shares, but the primary cause likely was the fraud lawsuit against Barclays; banks such as Morgan Stanley, Goldman Sachs, JPMorgan Chase and Citigroup all fell.
Participation again was weak at fewer than 600M shares changing hands at the NYSE.
Treasurys spent most of the session in the green, ending just below their highs; the yield on the 10-year note fell by 3 bps to 2.53%.