Brendan Rodgers' Celtic likely don't need any reinforcements to the deliver the domestic success that they're heading towards in the second half of the season. Nineteen points clear in the Scottish Premiership, their procession to the league title feels like a formality.

However, the January transfer window remains an important one with strengthening required ahead of summer qualifiers and the need to move players on who aren't quite first team calibre anymore.

Rodgers has already done some business, signing Ivorian midfielder Kouassi Eboue from Russian side FC Krasnodar. He also signed Mikael Lustig up to a new deal which will see him stay at the club until 2019, with his previous contract due to run out this summer.

What other business should be done? Who should come in and who should go out? Here are THREE ins and THREE outs that Rodgers should consider before the end of the transfer window...

In: Henry Onyekuru

Henry Onyekuru is a 19 year old Nigerian forward who could provide the attacking depth that Celtic need going forward.

They have Moussa Dembele and Leigh Griffiths but little beyond that and Onyekuru is player of quality who wouldn't necessarily need to play week-in, week-out to continue his development.

The teenager has scored 12 goals in 25 appearances for Belgian side Eupen this term, showing he has the ability required to make an impact in the Scottish Premiership. He's also scored six in his last 10 appearances meaning if he does move, the Bhoys are getting a player in form and ready to hit the ground running.

Heading into next year's Champions League with just two effective strikers would give Hoops fans pause for thought, so whether it's Onyekuru or another, Rodgers should be looking at attacking options sooner rather than later.

Out: Nadir Ciftci

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The former Dundee United man has never really settled into life at Celtic, often looking a step off the pace required to make it at the Bhoys.

Moving him on now is likely the best for all concerned. There is a talent there, it's just not consistent enough to meet the high standards and demands of the Scottish Champions.

The Turkish striker has not made a single start under Brendan Rodgers and only two substitute appearances, with the last coming way, way back in July.

It makes no sense for him to hang around if either the club or his agents can find a new home for him.

In: Tosin Adarabioyo

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Celtic are in the same unique position when it comes to Tosin Adarabioyo as they were when it came to the likes of Moussa Dembele and Joe Ledley.

Due to being a cross-border club in FIFA terms, the Bhoys wouldn't be required to pay the stiff compensation fee for his signature to take him from Man City when his contract expires, unlike clubs in England.

That contract is up in the summer so now is the perfect time for the Hoops to get him signed on a pre-contract agreement and potentially even bring him to the club early.

A strong and powerful young central defender, Adarabioyo has in fact played against Celtic this season in the UEFA Champions League.

A move for him would provide excellent competition for the likes of Erik Sviatchenko and Jozo Simunovic. Likewise, Brendan Rodgers is an ideal manager for young players to work under given his track record of developing starlets such as Raheem Sterling and Daniel Sturridge.

Out: Efe Ambrose

Like Nadir Ciftci, Efe Ambrose does not have a future at Celtic. He's been at the club for years now but a catalogue of errors and poor performances have blighted the many good showings he's had for the Hoops.

Faith in the defender is at an all time low in the Hoops support and a move away would likely suit all parties.

He hasn't played for Celtic since the away draw against Astana last July, one of only two appearances under Brendan Rodgers.

He'll likely always be a cult figure with the Celtic Park faithful due to his commitment and personality but in terms of a playing career, his time is up with the Bhoys.

In: Joe Gomez

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In European terms, Celtic's playing budget is tiny compared to most of the other Group Stage teams. That means they have to be creative in terms of recruitment.

One experiment that has worked well over the last 12 months has been the long-term loan signing of Patrick Roberts. Roberts, who was unlikely to get much - if any - game time at Manchester City, moved to Celtic last January on an 18-month deal that will see him remain at Celtic until this summer.

A similar move for Liverpool's Joe Gomez this January would likely be no bad thing for either clubs or the player himself. The young defender has just returned to full fitness after a year on the sidelines with a bad injury.

He recently featured in both of Liverpool's FA Cup matches with Plymouth but is unlikely to be seeing any Premier League action soon.

Still just 19 years old, an 18-month loan to Celtic would let him continue his development under an excellent coach and also give him vital first team experience as cover or competition right across the Celtic backline.

Out: Dedryck Boyata

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Dedryck Boyata is another defender at Celtic who is unlikely to have a future at the club. A regular under Ronny Deila, he's failed to make an impression on the first team this term, making just two starts for the Hoops.

The latest did come this past weekend in the Scottish Cup against Albion Rovers, but there's little to take from his performance given it was against a part-time team.

That may offer a glimpse of a chance of a future under Rodgers but the likelihood is that moving him on is the best case scenario, especially if Celtic do business at the back and bring a defender in before the deadline.