New Celtic signing primed for Hearts start as striker suffers injury amid transfer update

Cvancara was recruited on loan from Borussia Monchengladbach this week but has not played since November after a previous loan move to Turkish side Antalyaspor was cancelled due to a wage dispute.

However, the Czech Republic international has declared himself ready to play and O'Neill admitted that the 25-year-old could be thrown straight in from the start after Johnny Kenny returned from Bolonga with an injury.

Kenny was brought off the bench in the second half of the 2-2 draw with the Italian side in the Europa League on Thursday but is a doubt for the trip to Tynecastle.

"Johnny Kenny has picked up a calf strain, we're not sure [how bad it is]," O'Neill revealed in his Friday press conference.

"He's gone for a scan this afternoon. He might be a doubt. He felt it during the course of time he was on. We'll have a look again tomorrow and see how it is."

Fellow striker Kelechi Iheanacho has returned to training for the first time since picking up a hamstring injury in the Premier Sports Cup final defeat to St Mirren at Hampden on December 14 but the game may come too soon.

"I'm glad to see him back," O'Neill said. "It might be a bit of a stretch to start him but at least he's going to be available."

That leaves O'Neill with the choice between starting Daizen Maeda through the middle - as he did in Bologna - or giving Cvancara his debut from the start at the home of the league leaders.

"He could start on Sunday," the Celtic boss admitted. "He's available and he's ready to play. He has had a couple of training sessions now and he's looking pretty good. We'll see. What I don't want to do is put an awful lot of pressure on him thinking he is the answer to all our problems. That's not going to be the case. He'll need a bit of help himself and maybe we would hope to do something before this transfer window ends. We're still working on things and we're hopeful."

While Celtic are hoping to recruit further additions before the February 2 deadline, O'Neill admitted that Cvancara is likely to be the only new face at Tynecastle.

"I would hardly think before Sunday but we've got another week and I'm still very hopeful we'll get people in," the Northern Irishman added. "For me and the coaches here it's a bit of a juggling act.

"We're trying to concentrate on the games ahead, which is the most important thing, while still thinking about trying to get players into the football club we think can help.

"You can add another 15 players to the squad that might not improve it one jot. We're trying to look for that bit of quality, trying to get value for money, all of those particular things go into it."

Celtic are six points behind Hearts at the top of the Premiership and O'Neill admits it is a game they cannot afford to lose.

"It'll be massively tough," he said. "They've beaten the club twice this season and are in a great position.

"We've left ourselves with very little room to manouvre. We've got them now with a chance to reduce the gap and Hearts have a chance to extend the gap. Losing the game would be terribly disappointing and give us an awfully long way to go."