RONNY DEILA has impressed upon his players the importance of Celtic returning to the top of the SPFL Premiership tomorrow night.

The defending champions can overtake leaders Aberdeen with a victory over Motherwell at home, something Deila feels will give them a psychological lift as they try to repel the threat of the chasing pack led by Derek McInnes' side. Celtic have not been in first place since New Year's Day - when their match at Partick Thistle was postponed - and Deila believes they must make the most of the opportunity to return to the summit with Aberdeen inactive.

"That's an important thing," said the Norwegian. "You know the points you get they can't take away from you. You can think we have two games more [in hand] but that's not the point. We need to get the points and if we win now then we are ahead.

"If we are top of the league then they have to do something to get it back and we have to ruin it. We want to have it in our hands and that's why the two next games are so important for the league."

Deila, who confirmed an interest in Tal Ben Haim, the Maccabi Tel Aviv forward, reiterated his stance that Kris Commons would not be leaving the club this month, despite interest from Bolton Wanderers, and has not given up on Commons signing a new deal at Celtic. The former Scotland player threw his boots into the crowd following Saturday's match against Hamilton Academical but Deila believes that gesture wasn't necessarily significant.

"The situation is still the same," he added. "We are talking together and will see if something can be agreed. I haven't talked to him about that [throwing in his boots]. I've only talked to him about his situation which is very clear and we'll see what's happening in the next few days.

"I still think a deal can be done. I haven't given that up. He's a very good player and we'll see if we can do this for a longer period. We want him and he wants to stay. It's about the contract.

"It's hard to say how apart we are but we're not agreeing. And when you do not agree, you do not agree. So we'll see but we're in negotiations. If I didn't want him and he didn't want to stay it would be finished now. He's not leaving in January. We have to win the league. He's a good player and we want to keep the best ones."

Deila also apologised to Jackie McNamara after the Dundee United manager had expressed his dissatisfaction with the Celtic manager speaking openly about Gary Mackay-Steven prior to the winger signing a pre-contract agreement to join Celtic in the summer. Perhaps chastened, Deila was noticeably less bullish about the prospects of the player signing in January.

"This is not up to us. We'll see what happens but what we do know is he's coming in the summer. It's too early to say something else. We have a lot of good players here in that position also but we'll see what's happening this month."