Shares in the chain fell as Sainsbury's disappointed investors by also omitting to give much more detail about its proposed takeover of Argos owner Home Retail.
Sainsbury's like-for-like (LFL) retail sales for the third quarter were down 0.4% excluding fuel and also fell 1.8% including fuel.
That contrasted with a 0.2% rise in LFL sales excluding fuel at Morrisons in the nine weeks to January 3.
Shore Capital analysts said the Sainsbury's performance suggested the chain's ex-VAT food LFL sales were a little weaker.
"Such a performance would put Wm. Morrison Supermarkets'+ (MRW, House Stock) 0.2% positive LFL sales for the nine week period in even better light to our minds and perhaps suggest that Tesco UK (Hold) may also do a little better in grocery than our minus 2.0% expectation," they said in a note.
Soft furnishings and household goods retailer Dunelm (LON:DNLM) was 3.2% off as its latest trading statement underwhelmed investors.
Like-for-like sales slipped 0.8% in the 13 weeks to January 2, compared with the same period the year before, but that was weaker than expected.
But shares in Ted Baker were in vogue after the up-market fashion brand said sales rose by more than a tenth in the run-up to Christmas.
So, as the round of post-Christmas retail updates grinds on, there are still more winners than losers.
But that could all change as a string of high street names update the market on Thursday including Asos (LON:ASOS) , Burberry (LON:BRBY), Home Retail (LON:HOME), JD Sports (LON:JD.), Moss Bros (LON:MOSB), Mothercare (LON:MTC), Supergroup (LON:SGP) and - of course - Tesco (LON:TSCO).