The official, who was standing in front of the away supporters, was treated for a cut to the back of his head.
Steven Gerrard left as Liverpool's under-18s coach to take charge of Rangers, and Jurgen Klopp has been pleased with the start of his tenure.
Celtic have promised a full investigation after five people were injured trying to get into Celtic Park for the Old Firm derby on Sunday.
Olivier Ntcham's 62nd minute strike was enough for Celtic to beat Rangers and send Steven Gerrard home empty-handed in his first Old Firm derby.
Lyon completed a late move to secure the services of Celtic striker Moussa Dembele just ahead of the transfer deadline on Friday night.
Dembele is reported to be the seven-time French champions' main transfer target following the departure of Mariano Diaz to Real Madrid.
Hearts manager Craig Levein was taken to hospital on Monday morning but is recovering after receiving treatment, the club said.
Demetri Mitchell, 21, played 11 games for Hearts during the second half of last season after leaving Old Trafford on loan in January.
Rangers winger Jamie Murphy will miss the rest of the season after suffering a knee ligament injury, manager Steven Gerrard said on Wednesday.
Graham Arnold could tell over the phone just how much Mark Milligan will be revitalised by his shift to Scotland.
Steven Gerrard said artificial turf has no place in "elite football" after seeing one of his Rangers players injured in a game at Kilmarnock.
Wilson, who has scored four goals in 20 senior appearances for United, has been given no indication he has a first-team future under Jose Mourinho.
Rangers striker Alfredo Morelos will be available to play in Sunday's Premiership clash against St Mirren after he had his red card rescinded.
City have been leading the race for Australia international winger Arzani, with Melbourne City a sister club.
New Rangers boss Steven Gerrard said the "world is against" his club and has been for years after disagreeing with a number of decisions on Sunday.
Steven Gerrard was denied a win in his first Scottish league game as Rangers manager by an injury-time goal on Sunday.
Frank Lampard said he and Steven Gerrard have discussed the challenges of being first-time managers before their clubs' domestic campaigns begin.
Socceroos sensation Daniel Arzani could be lining up alongside Tom Rogic for the next two seasons as he reportedly nears a loan switch to Celtic.
Celtic's Odsonne Edouard has been handed a four-month suspended prison sentence and fines for his role in an air-gun incident while at Toulouse.
Southampton have signed Scotland international Stuart Armstrong from Celtic on a four-year deal for a reported £7 million.
Gerrard left Liverpool at the end of the 2014-15 campaign and headed for Major League Soccer side LA Galaxy before retiring from football in 2016.
A comprehensive list of all the champions, European qualifiers and relegated teams across the major leagues.
Celtic's Odsonne Edouard will not be weighed down by the record £9m transfer fee the Scottish Premiership side paid for him, Scott Brown has said.
Celtic have signed Odsonne Edouard from PSG in what the Scottish club said is the biggest transfer in their history.
Ejaria, 20, will arrive at Ibrox alongside coaches Gary McAllister and Michael Beale who also leave Liverpool.