Martin O'Neill used his first interview as Celtic's permanent manager to frame last season as a 'wake-up call' — a reminder that the Scottish Premiership is tightening around a club that once made title wins look routine. That is an honest and sobering assessment. The concern is whether Celtic are responding to it with the pace the moment demands.

O'Neill was confirmed in the post on 11 June, almost three weeks after the curtain came down on a season that ended in genuine drama. Celtic needed seven consecutive victories to overhaul Hearts on the final day and retain the championship by two points. It was breathless, brilliant — and perhaps a little too close for comfort for a club of Celtic's stature. His backroom staff were not publicly confirmed until a fortnight after his own appointment, the same day the players returned for pre-season. One coaching position has already fallen vacant with Gavin Strachan's departure to West Brom.

O'Neill, who turns 74 this year, has spoken candidly about the competing pressures of the new campaign. He acknowledged that Rangers are likely to strengthen, and that Hearts — who pushed Celtic to the wire — will not surrender their ambitions quietly. 'I felt every single time that we played matches last season the teams were getting closer to Celtic than perhaps ever before, certainly in recent times,' he told Celtic TV. 'Those are concerns.'

A squad that needs reinforcing, and quickly

The urgency in those words is entirely absent from Celtic's transfer business so far. At the time of writing, Celtic and Motherwell are the only two Premiership clubs yet to bring in a single new signing this summer. When you factor in departures — including loanees, the outgoings list could reach double figures — the squad is running thin before a ball has been kicked competitively.

The futures of Daizen Maeda, Arne Engels and Benjamin Nygren all remain unresolved. Losing any one of them would represent a significant blow. Losing all three would be a crisis before the season has even begun.

The contrast with Celtic's rivals is uncomfortable viewing. Hearts, despite finishing as runners-up, have overhauled their squad already — seven new signings confirmed as they prepare life under a new manager. Rangers, now guided by Derek McInnes following his switch from Tynecastle, have moved decisively. They have recruited Lawrence Shankland — Hearts' top scorer and a player who tormented Celtic on more than one occasion last season — and also brought in Scotland international Ross McCrorie from Bristol City. The market, it appears, is being shaped around Celtic rather than by them.

The Champions League factor

Pressing matters have a habit of clarifying the mind, and nothing focuses Celtic quite like the Champions League. Their play-off tie for a place in the league phase — first leg provisionally pencilled in for 18 or 19 August — is looming. The memory of last summer's collapse against Kairat Almaty of Kazakhstan, which destabilised Brendan Rodgers' tenure from the outset, will not have faded at Parkhead. O'Neill is unambiguous about what qualification means. 'Absolutely vital,' he said, adding that squad depth and mental preparation for those fixtures are among his foremost concerns.

That makes the current inertia in the transfer market all the more puzzling. Arriving at a two-legged play-off with a threadbare squad and unresolved personnel questions is not a recipe for the kind of disciplined European performance Celtic will need.

O'Neill himself admitted that the euphoria of the title win had not fully sunk in — hardly surprising given the pace at which he has been thrown back into the job. He described projecting himself forward to August or September, imagining watching Celtic from a distance, and deciding he could not face those regrets. That self-awareness is admirable. The test now is whether the club around him can match his clarity of purpose with comparable urgency in the transfer market.

The wake-up call has been sounded. Celtic have until mid-August to show they have truly heard it.

Frequently asked

When does Celtic's Champions League play-off take place?
Celtic's Champions League play-off first leg is scheduled for 18 or 19 August, with the tie determining whether they reach the league phase of the competition.
Who has Martin O'Neill signed for Celtic this summer?
As of the time of writing, Celtic have not made any new signings this summer, making them one of only two Scottish Premiership clubs yet to bring in a player ahead of the new season.
Why did Martin O'Neill decide to take the Celtic job permanently?
O'Neill admitted he was unsure immediately after the season ended, but said he imagined how he would feel watching Celtic move on without him and decided the potential for regret pushed him back into the dugout.