After unrest between supporters and the club threatened to derail last season, the board must now make good on its promises.
Nor should anyone assume O’Neill’s job is done: he delivered honours with a squad short on depth and quality, and he will rightly press for reinforcements.
Failing to strengthen risks a repeat of last year’s Kairat embarrassment and endangers their place among Europe’s elite.
Celtic were in the Europa League last term, bowing out to Stuttgart in the first knockout round—beaten 4-1 at home before a 1-0 win in Germany that wasn’t enough.
Even so, the victory in Stuttgart reinforced O’Neill’s European know-how, as did a win at Feyenoord and a ten-man draw in Bologna.
The tracksuit-clad veteran, though, wants those touchline celebrations in UEFA’s flagship tournament this season.
Missing Champions League revenue for a second straight year would tighten late-window spending.
And with Maeda gone and Arne Engels linked with a move, the pull of top-level European football could be crucial in persuading key players to stay.
It’s been more than 20 years since O’Neill last managed in the Champions League, qualifiers included. A two-time European Cup winner as a player with Nottingham Forest, he has six wins from 18 matches as a manager in the competition.
He has cleared Champions League qualifying twice in three attempts, reached the UEFA Cup final in 2003, and made the quarter-finals the following year.
Now a two-legged playoff on 18–19 and 25–26 August stands between a seasoned O’Neill and a return to the summit of club football, where he can showcase that European pedigree.
Before then, the Premiership title defence begins at home to Dundee on Monday 3 August, followed by a trip to Kilmarnock the next Sunday.