Just as Rangers' fuel levels started to dip into the reserve zone in the sweltering heat of Athens, up popped their new gas man. Djeidi Gassama had only been on the pitch three minutes when he showed brilliant technique to drill home a high angled ball into the Panathinaikos net on the hour mark. It restored parity in a match that was getting away from the Scottish side and permitted them progress into the third qualifying round of the Champions League. Gassama, a £2.3million signing from Sheffield Wednesday earlier this month, is already repaying what many saw as already bargain buy. He netted three minutes into his debut last week, scoring the second goal in a 2-0 win over Panathinaikos in the first leg at Ibrox, and is fast showing his credentials as a super-sub. The 21-year-old Frenchman will be a starter soon enough, once his fitness is up to speed. Perhaps even next week when Rangers' Champions League qualifying quest comes up against its next opponent in either Servette or Viktoria Plzen. This 1-1 draw in the Greek capital ensured a 3-1 aggregate victory over a Panathinaikos side left addled by regret. Rangers weren't very good in Greece. They passed sloppily, coughed up chances and rarely carried a goal-threat. They were indebted to some smart goalkeeping from Jack Butland but more so to some glaring inadequacies from their hosts, who not just in Athens but in Glasgow displayed profligacy in front of goal and softness at the back. Not that Rangers and their new head coach Russell Martin will grumble much. These are very early days for the boss and his players as he attempts to instil a fresh way of football in Govan. Some feared they would fall at the first hurdle but in a stadium that hosted the Olympics 21 years ago, they cleared it. Whatever technical deficiencies that were on show were cancelled out by grit, guts and determination. The likelihood is though that Rangers will need to raise the bar significantly if they are to reach the promised land. Their goal led a charmed life over the two legs and better teams than Panathinaikos lie in wait. Some explanation can be found in the fledgling nature of Martin’s tenure, but the cut-throat environment of the Champions League won’t mitigate for that The opening exchanges in Athens were similar to eight days ago in Glasgow. Panathinaikos started brighter, were crisper in possession and attacked with more intent. They forced Rangers into mistakes and just like at Ibrox, the Greeks failed to take advantage. By the ten-minute mark, Panathinaikos had forced a flurry of corners. Rangers stood up to an aerial bombardment but then so nearly turned the gun on themselves on 13 minutes when John Souttar left a long ball which Max Aarons dithered upon, allowing Facundo Pellistri to scamper clear into the visitors' penalty box. A heavy touch allowed Jack Butland to narrow the angle and the Uruguayan's shot was straight at him. Pellistri again misfired from a central position inside the box after Panathinaikos seized on some sloppiness from Nasser Djiga. Not helped by a poor bounce of the ball admittedly, but the ex-Man Utd man really ought to have at least hit the target. Captain and No 9 Fotis Ioannidis did at least test Butland with a smart header that was just too central to cause any damage. With the exception of a few counter attacks, Rangers spent most of the game in survival mode. The visitors could not get a handle on proceedings and benefitted from their opponents being toothless when asked to sink their teeth into opportunities. Martin would therefore be happy for his team to enter the sheds with their clean sheet in tact. This was not a strong first-half performance from his team, riddled with disorganisation and stray passes. The start of the second half followed a familiar pattern. Rangers could not keep the ball, Panathinaikos could not do anything noteworthy with it. By the 50th minute Rangers were already entering into a phase of game-management - time-wasting is what critics would call it. The home crowd booed in disapproval. Those jeers turned to cheers, however, on 54 minutes when Panathinaikos took the lead. Finally Rangers' resistance waned. The goal wasn't pretty but Panathinaikos did not care. The ball was swung into the box from Rangers' left and Filip Djuricic ambled in unmarked. He did not connect properly with his header but it had enough direction and spin to deceive Butland and slither into the net. The offside flag was raised initially but after a painfully long VAR check, the goal was awarded. Panathinaikos sensed blood. Souttar gave possession away cheaply on the halfway line and Djuricic stormed forward, only for his low cross to have too much juice on it and evade Ioannidis. What a moment that was, because on the hour-mark, Rangers levelled the match and restored their two-goal cushion in the tie. Nicolas Raskin drove forward, the ball came to Danilo and while his two efforts were blocked, Gassama caught the ball flush on the volley and it barrelled into the net via the far post. It was a surprising moment given that Rangers had been so inoffensive thus far, but entirely in keeping with the theme of this tie. Whenever Panathinaikos appeared like they were taking control, the Glasgow side pulled a rabbit out of the hat. The Greeks needed to respond. Ioannidis was again a couple of centimetres from connecting with a delicious delivery from out wide. The captain wailed in frustration, knowing that with 20 minutes to go, time was running out. Rangers had the final chance in stoppage time, but substitute Cyriel Dessers was thwarted by Panathinaikos goalkeeper Bartlomiej Dragowski with a sprawling save. Not that it mattered in the end. Rangers advance - for now.