Goals from Anthony Stokes and John Guidetti helped Scottish Premiership leaders Celtic to a 2-1 win over Dundee - but not before another anxious finale at Parkhead.
Paul Hartley's enterprising side were a match for their hosts in the first half but fell behind a minute before the interval when Stokes headed in a Kris Commons free-kick.
When fellow striker Guidetti scored his 10th goal since arriving on loan from Manchester City in the 54th minute it looked like the home side would cruise to three points.
However, four minutes later Dundee striker David Clarkson reduced the deficit, scoring in a seventh successive game for the Taysiders to equal the Dees record set by Alan Gilzean in 1964.
The anxiety emanating from the stands did not help the Hoops in the closing stages of the game - although they were not put under any severe pressure by the Taysiders.
Ronny Deila's side did enough to keep three points intact but will have to be sharper in their home Europa League clash with Salzburg on Thursday night, where they hope to leapfrog the Group D leaders whom they trail by two points. Once again, though, they will be without the ineligible Guidetti who is proving to be so important on the domestic scene.
Both sides had chances to score before Stokes broke the deadlock.
Less than a minute had elapsed when Dundee midfielder Greg Stewart found himself alone in the box after taking a pass from Clarkson but he fired wildly over the bar.
Moments later, after the Hoops defence again found themselves in a mess, defender Virgil van Dijk had to head clear Clarkson's goal-bound chip.
In the ninth minute, however, Celtic would surely have been ahead had Commons made better contact with his head on Stokes' near-post corner.
In the 27th minute Hoops winger James Forrest sent Guidetti through on goal with a defence-splitting pass but Dens Park keeper Scott Bain was quick off his line to block the Swedish striker's shot.
Then, as the rain began to cascade, Forrest escaped the attention of three Dundee players to drive into the box but his shot with the outside of his right foot was saved by Bain.
At the other end, Gary Harkins' corner was headed back across goal by Clarkson to defender Thomas Konrad, who headed over from point-blank range.
Stokes' goal came after the lively Forrest was brought down by Dundee's returning skipper Kevin Thomson on the by-line.
When Commons, featuring the first time since the 1-0 home defeat to Hamilton in early October after recovering from a muscle injury, drove the free-kick to the near post, the Irishman pulled away from Harkins to bullet a header into the net.
There was a flurry of Dundee activity after the restart but Guidetti's confident strike from 12 yards, after Adam Matthews had set him up, appeared to give the home side a decent cushion.
However, Paul Hartley's side responded immediately.
Defender James McPake had the ball in the Celtic net moments later from a Harkins free-kick but the offside flag truncated his celebration, before Stewart's powerful drive was deflected past the post.
However, Dundee did get a goal back in the 58th minute when, after Paul McGowan knocked the ball into the Celtic box to spark general mayhem, Clarkson pounced on the loose ball and forced it in from 10 yards.
The champions realised they had a game on their hands again and Charlie Mulgrew, stand-in skipper in the absence of suspended Scott Brown, came close with a decent drive after being set up by Stokes.
Celtic regained control but their one-goal lead remained fragile.
With 10 minutes remaining and tension increasing, Stokes set up substitute Callum McGregor, on for Forrest, but Bain made a decent save from the angled drive.
Beram Kayal, on for Commons, had the ball in the in the Dees' net in injury time but the flag was up for offside and in the end the Hoops did not need the extra goal - but they will undoubtedly need a better performance against Salzburg next week.