Nearly three weeks into the January transfer window and Celtic's solitary arrival remains a Bournemouth right-back, Julian Araujo, on loan.
Only Hibernian – yet to sign a player this month – have been less active in the Scottish Premiership.
Of Celtic's title rivals, Rangers have added three players and Hearts two, with a further – prolific striker Rogers Mato – on the way to Tynecastle.
A few days on from exasperated Celtic fans chanting "sign a player" during the uninspiring Scottish Cup win over sixth-tier Auchinleck Talbot, new arrivals at the reigning champions remain conspicuous by their absence as the number of targets linked with the club continues to rise.
Of those, the reported pursuit of Leeds forward Joel Piroe veered into farce.
Celtic's need for a striker is the most obvious and pressing priority. Johnny Kenny netted the opener against Talbot – and had a second chopped off for the thinnest of offsides – but Celtic require more quality up top, having not replaced Kyogo Furuhashi or Adam Idah.
If last weekend's cup tie was an audition for fringe players to stake a claim for a regular game in the Celtic XI, they failed miserably.
Michel-Ange Balikwisha – seen by interim manager Martin O'Neill as a number 10 rather than the winger he was signed to be – made his first start in four months and did little to convince that the millions he cost from Antwerp in the summer was a fee well spent.
Similarly, fringe midfielders Paulo Bernardo and Luke McCowan underwhelmed in a game where Celtic's best performer was 34-year-old James Forrest. Celtic's lack of depth is glaring.
"It's not putting the boot into Celtic, but when James Forrest – a wonderful talent, brilliant career, but now one of the oldest players – still looks your most creative spark, that has to be an overriding concern," noted former Hibs and Rangers midfielder Kevin Thomson to BBC Scotland.
O'Neill has said he remains "very, very hopeful" of adding to his squad before Sunday's trip to face Premiership leaders Hearts, who are reeling from injuries to Cammy Devlin and Lawrence Shankland, both ruled out for up to eight weeks.
Celtic supporters anxiously await any concrete transfer developments before a game where defeat would leave them languishing nine points off the top.
