His eyes remained fixed on the St Mirren goal, as if trying to understand what had just happened; how a victory that would had eased the pressure enveloping him had been snatched away in the space of three minutes.
The Paisley manager remained rooted for the final few moments of the contest, lingering for a few seconds after the final whistle as if dazed before stumbling down the tunnel as a cacophony of jeers tumbled down from the stands.
Lennon had talked before the game of fine margins but can scarcely have imagined how apposite his words would be. To suggest Thistle were anything other than worthy winners would be inaccurate, but the fact St Mirren were just nine minutes away from earning just a second victory in 13 games, since winning the League Cup will make it feel like an injustice.
Judging by his plea for clemency, it might also feel terminal. "I'm not naive and I know football is an emotional game but there needs to be a bit of patience," he said. "We are underachieving but let me tell you one thing: if my journey at this club ended tomorrow, I would have no regrets. I will take the experience, put it in my toolbag and carry it along with me for the rest of what is hopefully a long managerial career."
Among the lessons he might have learned is not to throw in a player who has only just met his team-mates. Stephane Bahoken, signed on Friday on a year-long loan from Nice, was included in Lennon's starting XI but lasted just 45 minutes. The French striker did offer a powerful, mobile presence and posed enough of a threat to suggest he will eventually be an asset; one bustle past Conrad Balatoni and prod at goal was thwarted by the recovering defender, who also blocked another effort from him.
The 21-year-old's withdrawal in favour of Gary Teale necessitated a change of shape and the alteration benefited the hosts, with the winger playing a key role in manufacturing an unlikely breakthrough. There appeared scant danger when he and David van Zanten found themselves penned in at the corner flag but somehow he smuggled a low ball towards the near post, where Kenny McLean pivoted to poke a tame effort under Scott Fox.
The goal was only the fourth Thistle had conceded in their first five games and left the visitors wondering quite how they were behind. After all, they had been the more menacing side for the opening 50 minutes and, had they been more ruthless, would have had a second league victory of the season secured by that stage. Kallum Higginbotham and Steven Lawless, in particular, tormented the St Mirren defence with the latter going closest to scoring when he lashed wide after a well-worked set-piece. Further openings were spurned by James Craigen and John Baird.
As painful as the concession was, it acted as the catalyst for Thistle. Higginbotham took centre stage as more openings were created, and he eventually equalised after assuming possession on the right. The Englishman exchanged passes with Steven O'Donnell before guiding a sumptuous finish across the helpless David Cornell from the apex of the area.
There was even better to come for Thistle when Kris Doolan set up Ross Forbes to slide a composed finish away from Cornell. "When we went a goal down I thought it was going to be the old sob story but we reacted positively," said manager Alan Archibald. "We want to get away from the cuddly toy image."