The S&P 500 has retested its lows seen in October, but a further decline from here would signal the bear market has much further to run, Robin Griffiths, technical strategist at Cazenove Capital, told CNBC.
"It absolutely may not go lower than it was on Thursday or the entire potential base pattern is broken and we've got to go through it all over again," Griffiths said.
The S&P 500 fell to an intraday low under 820 points on Thursday, which is weaker than the base seen in October. But the Thursday low still acts as a retest despite being weaker, Griffiths said.
(Watch the full interview with Robin Griffiths to the left).
Fresh closing lows below October's base would "signal this bear market is much much worse than the armageddon one that we've already discounted in share prices," he added.
The retest of October's lows for the S&P index had been expected by many analysts and could help to signal an end to resent declines, Griffiths said.
"We were always expecting a retest of the low, to be honest I was expecting it a little later than now, but last Thursday's retest was a valid retest," he said.
Griffiths expects the low to hold and for the S&P to "struggle up through a wall of worry and cynicism."
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