Inverness Caledonian Thistle FC tweeted the plea ahead of Wednesday night's away match against Dundee.
The message included the line: "We have no right to ask, but be there if you can."
It was posted just hours after ICTFC's Highland rivals Ross County beat Hamilton 3-2 in Dingwall.
If Hamilton had won, the Inverness club would have been relegated to the Championship.
County made the game free of charge to watch to home and away fans.

Taylor, 31, the first Kiwi double centurion against Australia, reached 290 before he was the last man to fall.
His score surpassed that of England's Tip Foster, who scored 287 against Australia in Sydney in 1903.
New Zealand made 624, their first 600 against Australia, but the hosts added 258-2 to lead by 193 with one day left.
Resuming on 235 in Perth, Taylor made the third-highest score by a New Zealand batsman. Brendon McCullum got a triple century against India in Wellington last year.
Taylor batted for nine and a half hours, facing 374 balls and hitting 43 boundaries before he was caught at deep square-leg by substitute fielder Jonny Wells.
That denied him becoming only the second batsman to score a triple century against Australia, after England's Len Hutton, who made 364 at The Oval in 1938.
It was New Zealand's fifth-highest Test team total, the record being set as recently as last year with 690 against Pakistan in Sharjah.
Having begun day four on 510-6 at the Waca, New Zealand were soon reduced to 587-9 before last man Trent Boult helped Taylor guide them past 600 and a first-innings lead of 65.
Australia lost Joe Burns for a duck in the third over but Steve Smith hit his fourth hundred as captain in only his fifth Test in charge. He shared an unbroken partnership of 212 in 55 overs with Adam Voges (101) who became the sixth centurion of the match.
Taylor celebrated both his century and double century on day three by sticking his tongue out in a message to his daughter.
He added he was "undercooked" going into the first Test, which New Zealand lost, after he was sidelined for six weeks by an injury to his testicles sustained in the nets in Zimbabwe in August.
"I felt I just needed to get back in the groove," Taylor said.
"You can either graft it out or go out and play your shots and the latter probably comes more natural to me.
"It's surprising what happens when you hit a couple off the middle, the feet start moving and the confidence comes flooding back."
Some observers highlighted the fact that Taylor was not congratulated by the Australian players at the end of his innings.
Australia opening batsman David Warner took to Twitter to explain that as Taylor was the last player to be dismissed, the home batsmen had to leave the field to prepare for their second innings.
A Scottish Premiership football club fighting relegation has appealed to its fans to show their support at the team's latest crunch game.
[NEXT_CONCEPT]
New Zealand's Ross Taylor struck the highest Test score by a visiting batsman in Australia as the runs continued to flow in the second Test.