Sainsbury was the only one of the 'big four' supermarkets to hold onto market share and resist the ceaseless rise of discounters Aldi and Lidl and upmarket grocer Waitrose.
As a whole, the sector enjoyed a better December of total market sales growing 2.3%, following two periods of poor industry sales of 0.8% and 1.3%.
A Christmas update from retail analyst Kantar Worldpanel for the 12 weeks to January 5th showed Sainsbury's has just about caught up with Asda as the second largest of the UK grocers as it managed to hold market share and outperform the market with year-on-year growth of 3.1%.
Sainsbury remained at 17.1% of the total UK sales in the period, with Walmart-owned Asda's slipping from 17.5% to 17.1%.
Tesco remains well ahead in the leading position but its market share fell from 30.4% to 29.6%.
Morrison's share of the sector dropped from 12% in the same period a year ago to 11.5% this time, with a decline in overall sales of 1%.
Privately held Aldi grew 29.4% and claimed a 4% share of the Christmas market, while Lidl grew 17.5% to a share of 3.1%. Waitrose grew 6.4% to a 4.8% market shares, the Co-operative grew 0.4% to a 6.1% share and Iceland grew 3.8% to a 2.2% share.
Looking at the shorter four-week section at the end of the period, broker Jefferies was surprised by the extent to which the discounters have not represented an incremental attrition to the UK majors.
"The Co-op, the UK number five player, appears to have been the major culprit here with strong sales growth of 2.8% - or a 160 basis points outperformance of the big four versus a previous average underperformance for 2013 of 250bps," analysts wrote.
Kantar noted that, as well as online sales, local convenience shopping continued to be another fast-growing weapon in the Big Four's armoury, with both Tesco Express and Sainsbury's Local enjoying double-digit growth.
Jefferies said the improved momentum for the sector "appeared to reflect a consumer willingness to celebrate over the festive season, but not across all grocery stores. The update contrasts with last week's British Retail Consortium update showing a weak Christmas but we note the reporting periods are different - with BRC including the first week of December, which we believe was very tough for the industry."
Jefferies pointed out that Sainsbury's had a particularly strong four-week Christmas period, with sales up 6.7%.
"The extent to which the previously weak trend snapped back over Christmas would suggest a major change in trading tactics."
Analysts said they believed Asda may have benefited from driving footfall after a very successful Black Friday event in late November.