SELF-HELP books are the stuff of publishers' dreams but if Ronny Deila is looking for any advice on how to deal with the stress of the last three days, he should look in the football literature section instead.
Gordon Strachan's autobiography has a crumb of comfort which might keep Deila going as his position as Celtic manager - and his reputation - comes under scrutiny following a 4-1 defeat by Legia Warsaw in the first leg of their Champions League qualifier.
Strachan has been in a similarly vulnerable position. Nine years ago the coach who is now in charge of Scotland suffered his own trauma in Europe as his tenure at Celtic began with a humiliating 5-0 defeat by Artmedia Bratislava. That led to the Glasgow side being knocked out of the Champions League, and without a place in the Uefa Cup to soften the blow. Celtic also experienced its worst financial results of that decade as a result of missing out on European revenue.
Strachan did gamble when his side was just 2-0 down in Slovakia, chasing an away goal which he felt would offer Celtic a lifeline in the qualifying tie. They did not get it and instead drifted out of the competition, albeit after winning the second leg 4-0.
In his 2006 autobiography, Strachan dwelt on the problems of replacing a successful manager but with a diminishing budget. He cited the £34,000-a-week wage of one of predecessor Martin O'Neill's signings which covered all three of his new recruits - Shunsuke Nakamura, Artur Boruc and Maciej Zurawski.
All those problems crystallised into one torrid evening in Slovakia, very similar to the conditions in which Deila's team evaporated in Warsaw on Wednesday night. The parallels between the two occasions are unmistakable. Strachan used six of the players who had won the Scottish Cup under O'Neill just eight weeks earlier, but introduced debutant Paul Telfer in a similar way to how Deila started Jo Inge Berget against Legia, just a two days after he signed on loan from Cardiff City.
In his book, Strachan dismissed accusations of naivety by eschewing damage limitation in Bratislava. "It could have paid off," wrote the coach, pointing to missed opportunities by Shaun Maloney and Aiden McGeady during that match.
Perhaps Deila is right to cling to the away goal scored by Callum MacGregor, then. It seemed at first like a misplaced sense of values when Deila spoke of how that solitary moment of joy still mattered after the way his side were dismantled following the seventh-minute lead provided by the young midfielder.
As Deila prepares for the return leg at Murrayfield on Wednesday, the Celtic manager is working in front of a backdrop of mistrust and apprehension, both about his ability as manager and about Celtic's immediate European future. It is hardly fertile ground for energising players and supporters to launch a comeback.
Strachan, though, has inadvertently offered some hope for Deila. The events of that night in Bratislava shaped the Scot and he went on to lead Celtic to the last 16 of the Champions League in both 2007 and 2008. "Almost every manager or player is bound to find himself on the wrong end of a thrashing at some stage of his career," Strachan wrote.
Strachan also recalled Brazil giving Jock Stein's Scotland a 4-1 thrashing in 1982 World Cup and suggested that perhaps David Narey's opening goal provoked Brazil. Perhaps MacGregor did the same in Warsaw.
Deila would not be the first Celtic manager to be caught out in Europe not long after their appointment. Neil Lennon had to suffer in Braga and Utrecht before he made the adjustments to his tactics and his personnel which delivered successive Champions League group-stage football. Liam Brady was also in charge of a Celtic side which was humbled by Neuchatel Xamax in the Uefa Cup 24 years ago.
Before Deila can attempt to put things right in Europe, however, he will send his Celtic side out against Tottenham Hotspur today. The friendly match - which is being held in Helsinki - will be Celtic's seventh friendly this summer.