Ronny Deila used the international break to reflect on a "stressful" start to his career as Celtic manager.

The Norwegian took over from Neil Lennon in June and was thrown into the crucial Champions League qualifying campaign the following month, which ended with fingers pointing towards the former Stromsgodset boss when the Hoops failed to get through the play-off stage against Slovenian side Maribor.

The fact that Celtic had been given a reprieve after losing 6-1 on aggregate to Legia Warsaw in the third qualifier when the Polish side fielded an ineligible player in the second-leg at Murrayfield, only brought more criticism as the Parkhead club dropped into the group stages of the Europa League which begin next week with a trip to Salzburg.

Following the 1-1 Scottish Premiership draw with Dundee at Dens Park - Celtic's fourth game without a win - Deila returned to his homeland to see his wife and two daughters before returning refreshed, reinvigorated and ready to go

Ahead of the visit of Aberdeen on Saturday, he told Celtic View: "It was important to get some reflection as it's been 10 stressful weeks with a high intensity.

"So to get some days off and reflect on where we are and where the road is going has been nice and I'm looking forward to the games now.

"We have done a lot of good things but there are also things we can do better.

"We need to sort out how we are going to get more improvement in the team and work on the issues we need to tackle, both offensively and defensively.

"It takes time. We have made progress but there is still a long way to go.

"The squad is strong and we have many interesting games coming up so there are big opportunities to get more improvement and better results."

Deila returned to a strengthened Celtic squad which left him "very satisfied".

Serbian striker Stefan Scepovic, 24, signed a four-year deal from Sporting Gijon on transfer deadline day while Swedish forward John Guidetti arrived on loan from Manchester City.

"I am very happy to get them in," said Deila.

"We have strikers but they are quite similar so to get in strikers who have different qualities is important.

"Now we have bought in two very exciting players up front and that will make the squad and the competition in the team better, and we need that because of the amount of games we play.

"I'm really looking forward to working with the whole group and getting their potential about."

Guidetti's deal was not completed before the transfer deadline but the move was rubber-stamped following an appeal to UEFA by the Scottish football authorities.

The 22-year-old scored 20 goals in 23 games during a loan spell with Feyenoord in 2011-12 which led Deila to declare his excitement.

He said: "He's a natural goal scorer. He had a fantastic season in Holland when he played for Feyenoord and then he was unlucky and had an illness.

"I feel we can bring him back to that level. I have seen him many times at City.

"We are going to get him playing games and then we will get a good player."