Hearts currently look like a side that "absolutely" could be relegated this season, according to former club captain Gary Mackay.
The Tynecastle club are 11th in the Scottish Premiership, above Hamilton Academical only on goal difference.
They were overtaken in the standings by St Johnstone after a 1-0 loss to the Perth club at home on Saturday.
"Absolutely," Mackay told Sportsound when asked if Hearts looked like a side that could go down.
"I think this week is pivotal. If we go into the Christmas period after the two games we have sitting bottom of the [Premiership], which in reality could happen, then there will have to be a lot of soul searching done by everybody within the football department and boardroom."
Owner Ann Budge told the club's AGM on Thursday that no contingency plans had been made in case the club dropped down a division, but confirmed most players' contracts contain relegation clauses.
The defeat by St Johnstone, who were without an away win in 16 matches stretching back to 29 December last year, was greeted with outrage at Tynecastle.
It was Daniel Stendel's first game as the club's new head coach, having been chosen as the replacement for Craig Levein, who was sacked in October.
The 45-year-old German and his team face champions and league leaders Celtic on Wednesday night followed by a trip to fellow strugglers Hamilton on Saturday.
They round the year off with the Edinburgh derby against Hibernian on Boxing Day and a home match against third-place Aberdeen, and Mackay believes the squad have to cope with the pressure of an important run of games.
"They're not really expected to do anything against Celtic but if they go to Hamilton with the same attitude as they showed on Saturday [against St Johnstone], there's only going to be one outcome and it's not a Hearts draw or victory," he said.
"They have to show more passion for the jersey they're wearing and understand that there's not many clubs that can turn out 16,500 supporters when you're sitting bottom of the Premiership.
"Some of the players just looked like they weren't capable of handling that pressure. Hearts are a pretty experienced squad, it's not as if they've got young lads there, the nucleus of the group is quite experienced. For me they have to handle it."