Ryan Stevenson and Kris Doolan both scored as they helped injury-hit Partick pull off a surprise 2-2 draw with Dundee United.
Jackie McNamara 's United were the clear favourites to pick up the points at Firhill as they took on a depleted Jags line-up missing seven first-team figures.
Gary Mackay-Steven even put the visitors ahead early on but their lead lasted just a quarter of an hour before Stevenson headed the hosts level.
Doolan then capped off a magnificent first-half display from Alan Archibald's side with a second goal just after the half-hour mark.
It was a different story after the break as United piled forward but it took them until the 73rd minute to find an equaliser as Celtic target Nadir Ciftci netted.
The result leaves Thistle in ninth but dents the Tannadice men's title ambitions as they drop five points behind leaders Aberdeen.
While United boss Jackie McNamara was able to name the same side which thrashed city rivals Dundee 6-2 on New Year's Day, Jags manager Alan Archibald did not have it so lucky.
Injuries, illness and suspension ruled out a string of regulars, forcing him to make five changes to the side which lost 1-0 to Motherwell on Thursday.
Doolan and Steven Lawless returned to the team, while youngsters Liam Lindsay and Declan McDaid were handed their first Thistle starts.
With injured left-back Jake Carroll on his way back to parent club Huddersfield and Jordan McMillan also ruled out, 20-year-old right-back Dale Keenan was forced to fill in on the opposite side as he made just his fourth appearance for the Maryhill men.
But the former Ayr defender got off to a nightmare start.
His first touch put Partick in trouble after only 30 seconds as he handed the ball straight to Ciftci. He sent Mackay-Steven racing through on goal but the winger shot straight at Paul Gallacher.
But his next mistake after 10 minutes was more costly as he stood still and watched as Ciftci clipped a fantastic ball over his head for Mackay-Steven, who this time made no mistake as he swept the ball into the far corner of the net.
Those blunders apart, however, Partick had themselves looked lively.
They got their rewards midway through the half as they levelled things up. Gary Fraser - who had himself shaken off the effects of a sickness bug to start - hung up a corner into the box and it was met by Stevenson's towering header.
Arabs stopper Radoslaw Cierzniak had come for the cross but was nowhere near it as the ball flew over his shoulder and into the empty net.
The Pole did better soon after though as he pushed away Doolan's first-time volley after Stevenson picked out his run to the back post.
But Doolan did beat the keeper after 33 minutes. Fraser fired over a teasing cross from the right towards the back post. Keenan was foiled by United full-back Sean Dillon as he looked to make amends for his earlier mistake but the ball did fall for Doolan to steer home from five yards out.
Cierzniak did get a strong hand to Lawless' fierce drive and then pulled off a wonder save from Fraser at the back post as he looked to finish after Doolan somehow mis-kicked Lawless' cut-back.
Ciftci is a clear talent but the 22-year-old's temperament could be the one thing which makes Parkhead boss Ronny Deila think twice. With little service, his frustration were clear as first he swiped at fresh air while trying to shoot from the edge of the box just after the break before then ballooning a 20-yard free-kick.
But he looked far happier as he drew United level with 17 minutes left.
Mackay-Steven caused havoc in the Jags ranks as he drove into the box before Conrad Balatoni hauled him down. Referee John Beaton did not have time to reach for his whistle, though, as Ciftci slammed the loose ball past Gallacher.
Sub Ryan Dow thought he had found a winner late on but saw his shot squeeze past the far post.
Why are you making commenting on The Herald only available to subscribers?
It should have been a safe space for informed debate, somewhere for readers to discuss issues around the biggest stories of the day, but all too often the below the line comments on most websites have become bogged down by off-topic discussions and abuse.
heraldscotland.com is tackling this problem by allowing only subscribers to comment.
We are doing this to improve the experience for our loyal readers and we believe it will reduce the ability of trolls and troublemakers, who occasionally find their way onto our site, to abuse our journalists and readers. We also hope it will help the comments section fulfil its promise as a part of Scotland's conversation with itself.
We are lucky at The Herald. We are read by an informed, educated readership who can add their knowledge and insights to our stories.
That is invaluable.
We are making the subscriber-only change to support our valued readers, who tell us they don't want the site cluttered up with irrelevant comments, untruths and abuse.
In the past, the journalist’s job was to collect and distribute information to the audience. Technology means that readers can shape a discussion. We look forward to hearing from you on heraldscotland.com
Comments & Moderation
Readers’ comments: You are personally liable for the content of any comments you upload to this website, so please act responsibly. We do not pre-moderate or monitor readers’ comments appearing on our websites, but we do post-moderate in response to complaints we receive or otherwise when a potential problem comes to our attention. You can make a complaint by using the ‘report this post’ link . We may then apply our discretion under the user terms to amend or delete comments.
Post moderation is undertaken full-time 9am-6pm on weekdays, and on a part-time basis outwith those hours.
Read the rules hereComments are closed on this article