CELTIC are closing in on the man Gordon Strachan believes he needs to resolve his left-back problem.

But the Parkhead boss today confirmed he will try to improve EVERY position in his team - if he can find the players and the money to do so.

Strachan insists that is no reflection on the side which clinched the club's third SPL title in a row. He simply considers it his duty as manager to try and make Celtic even stronger.

Most of the transfer speculation this summer has focused on recruiting more defenders, with Auxerre's Gabriel Tamas and Le Mans' Marko Basa the main targets until negotiations over cash stalled this week.

The pursuit of these central defenders was seen in some quarters as a threat to the positions of Gary Caldwell and Stephen McManus.

Caldwell was deployed as a holding midfield player when he came on during last night's 1-0 defeat by Cardiff. But Strachan emphasised the point that both men are Scotland regulars.

And, while he refused to speak about particular positions, he was more than happy to talk in general terms about why he wants to bring in more quality.

As he prepared for tomorrow's game against Porto, Strachan said: "I'm not talking about the centre-halves, so take that out of the equation.

"But I think I've got the right to try and get better players in any position where we feel we can afford to get better players. If I think I can get someone better than Paul Hartley, then I would do that.

"If there was someone better than Jan Vennegoor of Hesselink, I would do that. If there was someone better than Aiden McGeady, I'd do that, if we had the money.

"But if they are not there, we make people who are here better."

Finding those new players, and successfully negotiating the deals, has proved extremely difficult in this window with only Georgios Samaras and Paddy McCourt recruited so far.

Strachan has already thrown down the gauntlet to the men already here to make it four titles in a row, but has warned the challenge gets no easier.

"We've said to the players, right, here we go again," he said. "We know how tough it is going to be, that people want to beat you, that you will have hard games, you are going to get kicked, you are going to get criticised, you are going to have stress, sleepless nights - are you ready for it again?

"They were a little bit tired for the first 20 minutes against Fulham, understandable as we had played the night before then travelled up from Southampton.

"But their passion has been fantastic in the games we have played."

Strach confirmed he is every bit as hungry as he was when he arrived at the club three years ago.

He said: "It gets better, and the more you get of this, the easier it becomes to handle."

Strachan also explained his self-imposed communication blackout since the night Celtic clinched the title at Tannadice on May 22.

"People mentioned I've not spoken for a while," he said. "But I need to have a pre-season away from you lot (journalists). Sometimes when you do it (interviews) you can get stressed and it affects your coaching."