Kieran Tierney’s return against Motherwell was a welcome boost for Celtic, but Martin O’Neill still has a problem when it comes to cover for the Scotland international.

Tierney lasted 82 minutes at Fir Park before Jordan Lotomba replaced him. Liam Scales has also been used at left-back this season, while Landon Emenalo is still waiting to make his Celtic debut.

Considering Tierney’s injury history, Celtic should have entered the season with an experienced alternative ready to step in.

And with that problem still unresolved, the availability of a former Celtic player raises an interesting question about the club’s summer recruitment.

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Is Jeffrey Schlupp a free transfer option Celtic could have explored?

Jeffrey Schlupp remains without a club after leaving Norwich City in the summer, and the 33-year-old was certainly worth considering as a possible option for Celtic.

Schlupp made 18 appearances during his loan spell under Brendan Rodgers in 2025, including both Champions League matches against Bayern Munich.

He scored once, provided an assist and offered Celtic cover at left-back and further forward. His performances weren’t always convincing, but Rodgers knew what he could get from the former Crystal Palace player.

Schlupp also brought considerable Premier League experience, having won the title with Leicester City in 2016 before spending eight years at Selhurst Park. Celtic had already worked with him for several months. They knew his strengths, his weaknesses and how he handled the demands of playing at Parkhead.

With Schlupp available without a transfer fee, exploring his fitness and wage demands would have been a reasonable option for the club to consider.

Celtic’s Landon Emenalo decision makes the Jeffrey Schlupp situation interesting

Celtic’s failure to retain Marcelo Saracchi left a significant gap in O’Neill’s squad. The Uruguayan wanted to stay, and Saracchi subsequently revealed how determined Martin O’Neill was to keep him at Celtic.

Instead, Celtic signed 18-year-old Landon Emenalo on loan from Chelsea. The youngster arrived with an injury, has yet to make a competitive appearance and was omitted from Celtic’s Europa League squad.

Chris Sutton had already questioned Celtic’s decision to sign an injured Emenalo in September, pointing to Tierney’s fitness record and the youngster’s lack of senior experience.

His criticism was justified. Celtic needed someone capable of covering Tierney immediately, particularly with European football adding to O’Neill’s workload.

Schlupp’s previous spell at Parkhead meant Celtic wouldn’t have been starting from scratch when assessing whether he could do that job. His versatility was another attraction, although his injury problems at Norwich presented a serious concern.

Philippe Clement’s Jeffrey Schlupp verdict gives Celtic something to consider

Schlupp managed just nine Championship appearances for Norwich last season, with injuries severely disrupting his campaign. However, Philippe Clement spoke positively about the former Celtic defender despite the decision to let him leave.

Speaking to BBC Radio Norfolk in April, Clement said: “I’ve been impressed in the two weeks that he’s been training because you see a very experienced player, a good character also in the dressing room.”

The Norwich manager explained that Schlupp had struggled with fitness and that the club needed greater consistency at left-back. Those concerns would have been particularly relevant to Celtic, given Tierney’s own problems staying fit.

A player who struggled to remain available in the Championship was hardly guaranteed to provide O’Neill with dependable cover. Schlupp’s medical condition and wages would have needed careful consideration before Celtic entertained any short-term agreement.

But the club knew Schlupp, had seen what he offered under Rodgers and could have explored whether he was capable of contributing again. That was an option worth examining during a summer when Celtic were struggling to replace Saracchi.

O’Neill now finds himself in October with Emenalo still waiting for his debut and no established specialist left-back to challenge Tierney.

Schlupp wasn’t necessarily the answer, but Celtic should have ensured their manager had reliable cover long before the season reached this point.