​Football in Glasgow’s goldfish bowl has a habit of being unnecessarily dramatised, yet there is a case for saying a week in mid-September could have a defining impact on Celtic’s season.After spectacularly failing the first of three tests during this mini crucial spell, alarm bells are ringing among sections of an unconvinced support.Martin O’Neill’s side have the chance to right the wrongs of their sobering 3-0 Premier Sports Cup quarter-final defeat by Rangers at Ibrox when they host their city rivals in a rematch in the league on Sunday, but a Europa League opener with Ferencvaros comes first.Celtic fans are tiptoeing with trepidation into their first European action since their Champions League play-off collapse in Linz, a capitulation that has the same supporters questioning this team’s big-game credentials, especially after Sunday.”It’s strange you’re never asked about team selection when you win games,” O’Neill responded bullishly when asked about the outside noise. “We’ve been doing a fair amount of winning domestically now for quite some considerable time and we’ve won our league games so far. “It’s another big test for us on Sunday, obviously, but it’s amazing the number of times you’re not questioned when you’ve won.”McGregor laments Celtic’s ‘team of individuals’Celtic & Scotland legend McGrain diagnosed with Alzheimer’sVisit our Celtic page for all the latest news, analysis and fan viewsWhy Celtic fans still need convincingIn short: the aforementioned big-game results this season and the performance level under O’Neill since January.The 74-year-old’s remit last term was to end a chaotic, rollercoaster campaign on a high after the Wilfried Nancy debacle. He absolutely did that, winning the Scottish Premiership title and Scottish Cup.Celtic fans spent the aftermath of that double triumph torn over whether they wanted to watch their legendary manager head off into the sunset with two medals round his neck or have him lead the team into a fresh season. Even O’Neill was unsure.One thing supporters were united on, though, was wanting to see overdue progress in Europe and a better product on the pitch. It seems they are still waiting for that.There will be fans of rival clubs who will view those wishes as greed, given Celtic still continue to dominate domestically.However, supporters of the Parkhead side have spent the past decade being conditioned into watching their team clean up trophies while still delivering dominant, free-flowing football, hence the demand is there.O’Neill and his staff were largely given a pass last term during a season of intense turbulence. Fury was mostly directed towards the club’s hierarchy, but the manager and his backroom team are now not immune from scrutiny.The Celtic boss’s team selection has been questioned by fans and pundits, including one of his former players, Chris Sutton, in the wake of an abject derby display.Are Sutton’s ‘great concerns’ justified?[SNS]Below-par showings were forgiven last seas