It was a European run that kept Ange Postecoglou in a Tottenham job last season, despite poor Premier League form. Ultimately, winning the Europa League was still not enough for the Australian, who was sacked at the end of the campaign.
The Champions League has looked to be current boss Thomas Frank's saviour, with Spurs finishing fourth and jumping straight into the last 16 by winning five of their eight group matches.
This dominant victory in wintry conditions in Germany, thanks to goals from Randal Kolo Muani and Dominic Solanke, will ease some of the pressure on Frank, for now at least.
But this success may at least buy Frank some time, with an injury-ravaged squad avoiding two extra games in a daunting February fixture line-up that includes Premier League matches against three of the top four â Manchester City, Manchester United and Arsenal - as well as a game against Newcastle.
With Tottenham 14th domestically and without a win in five Premier League matches, their fans may have travelled to Eintracht Frankfurt fearing the outcome, but instead they witnessed an excellent display.
Simons thought he had given them a second-minute lead, only for the goal to be ruled out as Destiny Udogie had earlier been in an offside position and fouled his opponent.
Joao Palhinha had a header pushed wide, Wilson Odobert shot against the post, and Simons almost pounced on an error from home goalkeeper Kaua Santos.
Scores elsewhere briefly dropped Tottenham down to ninth and their own victory was in doubt when Frankfurt's Hugo Larsson raced through, but he could only blast against the crossbar from six yards out when it was goalless.
However, Kolo Muani quickly settled nerves after the restart with the vital goal against the side he played for in the 2022-23 season.
Spurs dominated the rest of the game, with Kolo Muani, Pape Matar Sarr and Romero all missing chances, although it did not matter as Solanke's goal saw Frank and his side celebrate victory and qualification.