REFEREE Willie Collum will take charge of the Scottish Premiership encounter between Dundee United and Celtic on Sunday.
The 36-year-old will oversee the lunchtime game as the champions and current top-flight leaders travel to Tannadice for their first post-split fixture (KO 12:30pm, live on Sky Sports).
He will be assisted by linesmen Alasdair Ross and John McCrossan while the fourth official will be John McKendrick.
It comes after one of Collum’s biggest career appointments to date when selected to officiate the Champions League quarter-final second leg between Monaco and Juventus at the Stade Louis II on Wednesday night.
He was the man in the middle for champions Hearts against Raith Rovers at Tynecastle last Saturday in the Scottish Championship.
The Religious Education teacher from Belshill will be under greater pressure to perform in his fifth Celtic game of the campaign after the controversy surrounding their Scottish Cup semi-final defeat to Inverness at Hampden last Sunday.
There were also three red cards and two spotkicks issued by Craig Thomson the last time the sides met in Tayside in a tempestuous Scottish Cup quarter-final.
Collum only officiated the Hoops a fortnight ago in their 2-0 victory over Glaswegian neighbours Partick Thistle – sending off Jags midfielder James Craigen and awarding a penalty converted by Kris Commons on the stroke of half-time at Parkhead.
He has not given any yellow cards in his last three games but has sent off two players during that time.
The North Lanarkshire-based official has only officiated Dundee United twice this term – their 3-0 win at Aberdeen on the opening weekend and 2-0 home defeat to Tayside rivals St Johnstone in February.
He has only overseen two encounters between Celtic and Dundee United in the past – the Hoops’ 3-1 win at Parkhead on the final day of last season and a 2-2 draw at Tannadice back in November 2012.
Collum is widely renowned for issuing plenty of cards in domestic games – despite his reluctance to do so in European outings – and is often the centre of controversy but is regarded as a fit and highly rated official who tends to get the big decisions right.
However, he endured a controversial start to 2015 domestically.
Collum awarded four penalties and sent off four players in his first two matches of the new year but saw the red cards he gave to St Mirren’s Kenny McLean and Motherwell defender Stephen McManus overturned by the Scottish Football Association’s judicial panel.
Collum was then dropped from the Premiership for two weeks before he and assistant referee David McGeachie failed to award a goal when Adam Rooney’s shot struck the underside of the crossbar before bouncing a foot over the line in Aberdeen’s 3-0 win at Hamilton in February.
He was also slammed by Hibernian boss Alan Stubbs last month for failing to spot a foul by Lee Wallace on Paul Hanlon in the build-up to Kenny Miller’s clinching goal for Rangers in their 2-0 win at Easter Road.
Overall, he has issued a massive 121 yellow cards, a league-high 15 red cards and 16 penalties in 41 games in all competitions this season.
Glasgow-born Collum – a father to three daughters – first took up the whistle at the age of 14 and has been a Category One official since June 2004.
He was promoted to the Scottish Premier League a year later and was first included on the Fifa list of international referees in 2006.
Domestically, Collum – who refereed the 2013 Scottish Cup Final and 2012 Scottish League Cup Final as well as several domestic cup semi-finals – is now regarded by many as Scotland’s leading whistler, overtaking Craig Thomson in that respect.
Meanwhile, on the European front, he has been a Uefa Category One official since 2012 and has officiated Bayern Munich, Juventus and Barcelona already in the Champions League this campaign as well as two European Championship qualifiers in an international capacity.
At the end of last month, Collum was at the helm for the friendly between the Netherlands and Spain in a repeat of the 2010 World Cup Final.
Dundee United lost three of their four meetings with Celtic last month including the Scottish League Cup Final at Hampden Park and the Scottish Cup quarter-final replay at Parkhead.
Jackie McNamara’s fourth-placed team – who have only won one of their last 12 games – were thumped 6-1 back in August but did come out on top in the last league encounter at Tannadice.
Celtic – who are five points clear of second-placed Aberdeen with a game in hand – face Dundee at Dens Park on Wednesday night before returning to the City of Discovery again on Sunday.