NEIL LENNON is considering changing the way his side defend set-plays after watching his men concede numerous times from corners and free-kicks into their area.

The Celtic manager believes that his side have to brush up on all areas of their defending after shipping 21 goals in their last nine games, earning just two wins from those matches along the way.

He concedes though that as well as his players taking on more personal responsibility for defending their goal, he too may have to consider his defensive set-up.

"These are the dirty bits of the game that we should do better," Lennon said.

"The first goal [against Sparta], Chris (Jullien) gets first contact on it and we don’t deal with the second phase which is down to us. That’s something we should have dealt with no problem.

"The third goal on the counter attack, we’ve got enough bodies there to deal with it but we don’t track the run. That’s individual errors – switching off.

"It all comes from us being in a very good position at a set play. Even the last goal we’ve got enough numbers back and maybe at that stage they have the feeling that the game’s got away from them.

"Certainly we could do things better in transition – individually and collectively and certainly on the set plays.

"It’s maybe become a bit of an issue for them. They’ve just got to be confident and trust themselves to deal with it.

"We didn’t have a problem with it last year but for some reason it’s become a problem this year.

"We’re working very hard [to change it]. I may look at it differently the way we set up at set players defensively in terms of the man marking side of things.

"We might change that. We’ll have a look at it. It’s something we need to definitely improve on."