Neil Lennon would have been quietly fizzing about Celtic's failure to bring in a central defender in the January transfer window.

It was made abundantly clear that the Hoops were in the market to replace Christopher Jullien following the knee injury he picked up at home to Dundee United back in late December. And the club had ample opportunity to do business.

Now, granted, Preston centre-half Ben Davies was basically a stick-on to join on a pre-contract before Premier League giants Liverpool swooped in at the last minute and bought the 25-year-old outright for around £1.6million. But we can't say that fee would have been breaking the bank at Parkhead, either.

As it happened - and despite the manager hoping to tie down a loan signing at the very least to go with Everton's Jonjoe Kenny - no new faces were brought in to bolster the heart of the defence. A definite source of frustration for the soon-to-be former Scottish Premiership champions.

So what do they do now? It's fair to say Kenny looked comfortable on his debut in a 4-0 win over Kilmarnock at Rugby Park in midweek. They also have Kris Ajer now available to head back into his typical spot as centre-half where he would usually have Jullien alongside him.

The question then becomes who does Lennon pair alongside the Norwegian for this afternoon's clash with Motherwell and, perhaps, for a run of matches beyond today? It cannot be loan man Shane Duffy.

The Irishman has toiled as a Celtic player this season despite heading to Glasgow with serious expectations hanging around his neck as a Premier League player. Neither Duffy nor the club hierarchy will be even close to satisfied with how his spell has turned out and it is only a matter of time until he heads back down south to Brighton - or wherever next - only to be considered a flop in Scottish football.

Meanwhile, while Duffy has been struggling, one youngster has flourished when called upon - and he has been called upon for some big matches - in 21-year-old Stephen Welsh. The Scotland youth cap has been trusted to start against Rangers and AC Milan, he has played against Lille twice from the bench and has looked composed each time.

Of course, still considered a kid in the grand scheme, Welsh does have a lot of work to do. A lot of growing to do in the position. Especially in a tumultuous Celtic season where criticism follows every single week, perhaps more so than usual. But with a 23 point lead in the league table the difference between Celts and their rivals Rangers, now is the perfect time for Lennon to give the younger players their chance.

Welsh was no-nonsense, confident and impressive against Killie on Tuesday evening. And helped his side to a clean sheet, which has been a rarity this season for Celts. The least his manager could do is allow him the opportunity to stake his claim for a regular slot. What harm will it do? He does not have the same pressure following him as Duffy does. He has the chance to learn from an international footballer beside him in the back-four. All Welsh's inclusion can do is help him get minutes under his belt if he really is considered one for the future.

It is the same argument, really, for the likes of forgotten wonderkid Karamoko Dembele. For Conor Hazard. For Luca Connell and Ewan Henderson. If any of them are ever really to make the breakthrough, they must be trusted now. Welsh, certainly, has earned that trust so far.