In the end, the bonus-point win they needed to give themselves the best possible chance of making the Heineken Champions Cup quarter-finals was delivered but not after a scare when the eliminated Welsh side reduced the gap to just four points in the closing ten minutes.

The Scots appeared to have it in the bag when they sealed the bonus point after an hour but it took George Horne’s 77th-minute try to calm the pulse rates around the stadium.

Dave Rennie’s side may yet need  to pick something up at Saracens on Saturday to get that spot in the knockout stage for only the second time but this workmanlike and at times strained showing from the home side brought a three-game losing streak to an end and took their Pool 3 tally up to 19 points.

George Horne dives over in the 77th minute to give Glasgow breathing space. Picture: SNS/SRU

There was some confusion an hour before kick-off when the official team sheet showed Scotland lock Jonny Gray named as a second-row starter. He had been withdrawn on Friday morning with a shoulder injury and it soon emerged that there had been no recovery and the team list provided was incorrect, Scott Cummings packing down alongside Rob Harley as the latter became the first man to reach 200 Warriors appearances.

The loss of two back-row players in the first ten minutes was not the start coach Dave Rennie would have wanted as first Matt Fagerson and then co-captain Callum Gibbins were forced into early departures, with Tim Swinson and Chris Fusaro brought on.

The wet and windy conditions took some time to get used to but slowly Glasgow began to get a grip on proceedings without ever clicking fully. It was nearing the half-hour mark before the breakthrough finally came, hooker Grant Stewart finishing off a controlled driving maul and Brandon Thomson adding the extras.

That kickstarted the Warriors into life as Tommy Seymour made a thrilling break, brushing off a poor tackle from Matthew Rees and scything through the Cardiff defence. The Scotland wing was hauled down and Swinson was repelled just short of the Cardiff line.

They couldn’t hold out for long as Ali Price’s popped pass was hit at the perfect angle by Cummings and the lock crashed over.

It had taken longer than they would have liked but that kept the home side on target for the four tries they desperately craved.

There was a twist in the tale of the half, however, as Cardiff gave themselves a sniff when, three minutes from the break, Owen Lane and Dan Fish combined down the right and the try was awarded despite a marginal call on an offside following Lane’s initial chip ahead before he regathered from his full-back to score.

The conversion was missed to keep Glasgow nine points clear at the turn and they were soon back on the front foot and driving the Welsh side back on their heels, although a lost lineout eased the pressure on the visitors.

The resistance lasted only until the 49th minute, though, as Fusaro was acknowledged as providing the final touch as Glasgow got another maul on an unstoppable roll.

Thomson’s skimmed conversion sneaked over from out wide and the Warriors were on the verge of making it job done with half an hour to go.

Cardiff weren’t prepared to crumble, however, and struck with a beautifully worked try as slick hands put centre Harri Millard in at the right-hand corner. Minutes after the  conversion attempt sailed wide the crucial moment came as that all-important fourth try was duly delivered as prop Oli Kebble squirmed over after a couple of sharp punches at the Welsh line.

Thomson converted to stretch the lead to 18 points but the buffer was cut yet again as Cardiff pieced together another impressive set of handling, Millard this time providing the scoring pass to flanker Josh Navidi, and sub Jarrod Evans converting.

Languishing second bottom on just four points, the visitors had nothing at stake but Rennie’s pre-match forecast that could be more of a worry than a comfort were confirmed as John Mulvihill’s men continued to come at the hosts with verve.

The cat was really set amongst the pigeons when Lane crashed between the posts for his second of the afternoon after more good work by Millard but Glasgow kept the ball down where it needed to be as the clock ticked down and replacement scrum-half Horne scurried over from close range to a loud exhalation of relief from the home crowd.

Rennie was a relieved but also  mainly satisfied man after the final whistle.

“We were actually talking probably ten minutes earlier, when we coughed up possession and then got penalised. We always felt that they could still come back into the game,” said the Kiwi coach of the Welshmen’s late rally.

“I thought they attacked really well. We’ll have a close look at some of that defensive stuff – there was a couple  of really soft tries and some really  passive defence.

“But I thought with ball in hand  we did a really good job tonight. I thought we were a lot more direct, made a lot better decisions and were a lot more patient. As I mentioned it paved the way from what the boys did up front.”

On those earlier injuries, Rennie reported: “Obviously we lost a  couple of reasonable players. Cully [Gibbins] didn’t look too good, and he’ll be doubtful for next week, definitely. Cully’s initially was knee, but it might be more sinister than that. Matt was shoulder.”

Glasgow 33 - 24 Cardiff: Warriors relieved to get over the line