With the disappointment of their Champions League qualifying defeat to Braga still fresh in the memory, the Hoops were well aware a positive reaction was required against the Dutch side.
Juarez, who also netted against Braga at Parkhead, is clearly enjoying the European nights in front of a home crowd and bagged the opener, before Samaras added a second to put Celtic in the driving seat ahead of next week's return in Holland.
Daniel Majstorovic made his Celtic debut when he was drafted straight into the side in place of the suspended Jos Hooiveld to partner Glenn Loovens in the heart of defence.
Utrecht headed into the clash having already comfortably overcome SK Tirana and Lucerne in previous rounds of the competition.
But it was Celtic who could have claimed an early advantage when Marc-Antoine Fortune raced past Mihai Nesu on the right flank before whipping a cross to the feet of Scott Brown only for the captain to rifle wide of target from 12 yards.
At the other end, Utrecht were not too far away when Jacob Mulenga tried his luck with a volley which fizzed across the face of goal and past the post, before nodding over after being set up by Jacob Lensky.
Celtic still looked dangerous and Samaras shrugged off his marker only to see his effort blocked at the near post, before the ball fell kindly for Shaun Maloney but he was denied the opener from close range by an impressive save from goalkeeper Michel Vorm.
The Dutch were then dealt a blow when Mulenga appeared to pull up and was replaced by Edouard Duplan.
The breakthrough came after 19 minutes when Beram Kayal supplied a deep pass, which Samaras dummied and allowed to run on for Juarez, and he left the goalkeeper with no chance when he lashed high into the back of the net.
Celtic were celebrating again when they doubled their advantage with 34 minutes gone.
Cha Du-Ri was the supplier with a cross from the right, picking out Samaras on the corner of the six-yard box who gratefully rammed home.
There was far from a capacity crowd at Parkhead but those who did make the effort were clearly impressed by what they saw as they chanted boss Neil Lennon's name.
Utrecht did try to hit back before the interval but a volley from Dries Mertens did little to trouble Lukasz Zaluska in the Celtic goal as the effort trundled harmlessly past the upright.
The visitors knew an away goal would help keep the tie alive and they almost pulled a goal back on the hour mark when a looping header from substitute Duplan was just touched over the crossbar by Zaluska.
Nana Asare then had a go with a shot from distance but the effort lacked power and was well off target anyway as the visitors desperately attempted to haul themselves back into the game.
Celtic made a change for the final 20 minutes when the impressive Kayal was replaced by James Forrest.
Forrest could have made an almost immediate impact on the tie with a point-blank header that the Utrecht goalkeeper did well to smother on the line.
There appeared to be no way back for Utrecht and they failed to take advantage of a late corner when Alje Schut could only muster a half-hearted header which fell well over the crossbar.