Here, the PA news agency looks at the Hoops' previous matches against Romanian opponents.
Celtic 2 Politehnica Timisoara 1 ( September 17, 1980)
Celtic's first European tie against Romanian opposition brought a narrow European Cup Winners' Cup victory.
Golden boy Charlie Nicholas scored a first-half double – the first when the keeper fumbled a Davie Provan cross, the second from a Murdo MacLeod chip – to give the rampant Hoops a comfortable half-time lead.
However, Celtic lost their way in the second half and with 10 minutes remaining, Adrian pulled a goal back for the visitors to give the Glasgow side a tough task in the second leg.
Politehnica Timisoara 1-0 Celtic (October 1, 1980)
The Hoops exited the competition in controversial circumstances on away goals after the 1-0 defeat left the aggregate scoreline at 2-2.
Defender Roddie MacDonald and striker Frank McGarvey were both sent off by Greek referee Nikolaos Lagoyannis, who made Celtic play against the wind in the first half even though skipper Danny McGrain had won the toss and chosen the other way.
Dan Paltinisanu scored a late winner after it looked like there had been a foul on keeper Peter Latchford.
Celtic 2 Astra Giurgiu 1 (October 23, 2014)
Stefan Scepovic scored his first goal for Celtic as the Hoops made hard work of beating Astra Giurgiu 2-1 in their Europa League clash at Parkhead.
The Serbian striker signed from Sporting Gijon for a reported £2.3million in the summer but was only playing because John Guidetti once again had to drop out as he was not registered in time following his loan move from Manchester City, and he missed two sitters early in the second half.
But he made up for that when he headed in an Anthony Stokes free-kick in the 73rd minute before midfielder Stefan Johansen made it 2-0, only for Gabriel Enache to pull a goal back to ensure a nervy ending.
Astra Giurgiu 1 Celtic 1 (November 6, 2014)
Celtic were denied early qualification for the Europa League group stages as they were held to a 1-1 draw by Astra Giurgiu in a fog-bound Marin Anastasovici stadium.
The Hoops were heading for the last 32 following Johansen's brilliant strike after 32 minutes in Romania .
Scepovic missed a good chance to double Celtic's lead and Charlie Mulgrew saw a shot pushed onto the post two minutes before William De Amorim equalised in the 79th minute with a curling shot which beat Craig Gordon.
Cluj 1 Celtic 1 (August 7, 2019)
Celtic overcame a first-half scare in Cluj to draw 1-1 and keep their Champions League bid on track.
The home side struck first when Mario Rondon slotted home just before the half-hour mark.
However, the tie turned in favour of Neil Lennon's side when James Forrest quickly levelled after playing a one-two with right-back Hatem Abd Elhamed before driving in off the post.
Celtic 3 Cluj 4 (August 13, 2019)
Despite an encouraging first leg in Romania, Celtic crashed out of the Champions League in the third qualifying round after twice letting a lead slip in a 4-3 defeat by Cluj.
Lennon's side made a great start to the second half to go 2-1 ahead through goals from Forrest and Odsonne Edouard but skipper Scott Brown's handball allowed Billel Omrani to net from the spot.
Ryan Christie quickly restored Celtic's lead but Omrani levelled again on the rebound in the 80th minute to put the Romanians ahead on away goals.
George Tucudean then netted with the last kick of the game to seal a 5-4 aggregate win.
Celtic 2 Cluj 0 (October 3, 2019)
In the first meeting of this current Europa League campaign, Celtic got their revenge with a comfortable 2-0 win at Parkhead.
French striker Edouard headed in the opener in the 20th minute as the Scottish champions dominated amid cascading rain.
Attacker Mohamed Elyounoussi added a second on the hour mark with a deflected drive to seal a well-deserved win.