Liverpool vs. Man United referee has sent off nine players this season
The referee of Thursday night's Europa League round-of-16 first leg between Liverpool and Manchester United has brandished nine red cards and 138 bookings in 25 matches season.
Spanish official Carlos Velasco Carballo will oversee the match between the two Premier League rivals at Anfield.
Carballo, 44, has handed out four red cards in his last six games, including a sending off in Deportivo's 3-3 draw with Malaga which also saw nine bookings.
United defender Chris Smalling and Liverpool full-back Alberto Moreno are both one booking away from a suspension.
Carballo, who has been a referee since 1988, has overseen the 2011 Europa League final and also officiated at Euro 2012 and the 2014 World Cup.
In July 2014, Carballo faced heavy criticism for his inability to control Brazil's quarterfinal defeat of Colombia.
Carballo showed just four yellow cards, despite blowing for 54 fouls, with a number of heavy challenges on show, including a tackle which saw Neymar ruled out for Brazil with injury.