If this football management malarkey doesn't work out for Brendan Rodgers, there's a career in the motor trade beckoning. At an unnerving Dens Park on a chilly Sunday, the ringing of boos at full-time had made way for the Celtic manager comparing his beaten Celtic team to a Honda Civic. No offence to Honda Civic drivers. "There's no way you'll go into a race and be given the keys to a Honda Civic and say, 'I want you to drive it like a Ferrari'. It's not going to happen," he said. An eye-opening public broadside aimed at his misfiring Celtic team, a collective Rodgers has openly made clear on several occasions is not to the standard he would wish for a domestic and European assault.

So, to Thursday. Another game. Another post-match news conference. Another mention of the dreaded Honda Civic. But this time his team had graduated towards becoming a Range Rover Sport on the back of a spirited 2-1 comeback win over Sturm Graz in the Europa League. "We weren't quite the Ferrari, but a Range Rover sport I'll go for," Rodgers said, grinning. "Hopefully we have no more Morris Minors in the performance. Not that they are a bad car." At risk of one final car reference, this was a game where the wheels threatened to properly come off for Celtic. A tricky tie which, at half-time, conjured a palpable feeling of angst to go along with the foreboding which carried fans into the contest.

Just a meagre one goal and one point from two Europa League games isn't a great return for a team who started this season shooting for the Champions League. Rodgers' public unhappiness at his squad has added to the malaise he was quizzed about pre-match. That's before you touch on an underwhelming league campaign which has them five points behind leaders Hearts. The Rangers implosion on pretty much every front has been the one saving grace. Fast forward to the Parkhead screen clicking round to 26 minutes. Kelechi Iheanacho had hirpled off injury. Kasper Schmeichel has been beaten from distance by a Tomi Horvat thunderbolt. Right-back Alistair Johnston, on his return from injury after two months out, is haring after a ball heading towards his own goal. A grimace, a clutch of the leg, and off he goes, too. It's at this point Celtic's character and mettle would be tested to its maximum. Unlike at the weekend, they handled it well.

It took until the 61st minute for the first wave of relief to come as Liam Scales swept the ball in. Benjamin Nygren's strike three minutes later put Rodgers' side on the road to redemption. "Sometimes with players you have to be harsh to be clear," said the Celtic boss of his post-match comments on Sunday. "And you hope that you get that reaction.

"These players know I'm with them always. I spend my life dedicated to making this team better, to helping the club progress. At the weekend it wasn't good enough.

"I said before the game to the players, we've really got to show leadership now. In my experience, when those types of players are under pressure, they progress.

"And you could see from the weekend coming into this game - the progress in the team was so good, individually and collectively. When you have a setback, like the weekend, those leaders show the motivation to go again, and we saw that tonight."

The key to Celtic's victory lay in the transformative approach to their attack. Only four goals had been scored in their preceding five games. That Morris Minor could have driven to Tayside and back five times over and they'd still not have scored at Dundee. Against Sturm, particularly in the second half, it was almost a throwback to Celtic of old. Almost. Twenty shots, seven on target, 136 final third passes. A rampant expected goals (xG) of 4.24 - the highest of any side in the tournament this season. Much of the joy was found down the left. Kieran Tierney, yet to show many signs of the rampaging full-back who left for Arsenal since his return, was given licence to advance. He was also joined out there by Sebastian Tounetki and Reo Hatate. Johnny Kenny was hurled on early doors for the injured Iheanacho and provided the focal point Celtic needed. Nygren could and should have had more than one goal. Perhaps one of the other key factors was the display from Arne Engels. The man who reportedly cost £11m last year has only started a third of games this season. He was an influence for good against the Austrians, swinging in eight crosses, creating five chances and providing an assist.

"I'm really happy for Arne Engels especially - it was great to see him back and playing really well," former Celtic defender Johan Mjallby told TNT Sports. "The character Celtic showed was really impressive. They could have easily caved in given the atmosphere around the club, the early injuries, and going a goal down. But they never panicked and kept on going."

Nobody at Celtic will - or should - be getting carried away, though. As credible as they were on what could have been a dour night, it was not a perfect performance, and the ghosts of Dens Park will not be exorcised so promptly. Arguably Celtic's biggest game of the domestic season is now almost upon them. A trip to Scotland's capital beckons on Sunday to take on a Hearts side who, with a victory, could pull eight points clear. It's an astonishing prospect which would have seen unfathomable as Celtic limbered up to start their season. They will travel east minus Johnston, Iheanacho and potentially Cameron Carter-Vickers. What they will take with them, though, is a renewed sense of self-belief, and something tangible to suggest they've got it in them to knuckle down. That's what this title-winning juggernaut has been built on. Getting the job done. They did it against Sturm, now it's time to repeat it.