Ref Watch is back to debate another selection of controversial decisions from some of the weekend's Premier League matches.
Former top-flight official Dermot Gallagher has been in the Sky Sports News HQ studio to analyse a number of contentious calls from weekend.
From debatable goals and penalty decisions, to red cards, concussion laws and changing a player after the teamsheets have been handed in, we have it all covered in this week's edition.
MATCH: Hull v Arsenal, Premier League, Saturday
INCIDENT: A penalty was awarded late in the first half when Jake Livermore was deemed to have used his arm to block a goal-bound shot from Francis Coquelin.
SCENARIO: As well as giving the Gunners a spot-kick, referee Roger East issued a red card to Livermore.
However, Alexis Sanchez took the penalty before Livermore had left the field of play. The Arsenal man missed - should it have been retaken?
DERMOT'S VERDICT: 'HARSH' RED CARD & PENALTY SHOULD HAVE BEEN RETAKEN
DERMOT SAYS: The question to answer is whether the handball has denied a goal, effectively stopping the ball going into the net. On this occasion, the goalkeeper is behind the player. The referee has made a judgement that the ball is going to end up in the net. I think it's harsh. That's a big, big call, to assume it's stopped a goal.
Regarding the actual taking of the penalty, the fourth official is looking straight at it [Livermore on the pitch] - he should alert the referee. It's a very bad error. The law is the law and the law states that the player must be off the field of play when play restarts. We can't defend the referee when he's actively broken the rules.
MATCH: Everton v Middlesbrough, Premier League, Saturday
INCIDENT: A ball in from the left flank sees Middlesbrough forward Alvaro Negredo and Everton goalkeeper Maarten Stekelenburg both challenge for the ball in the six-yard box.
SCENARIO: After the aerial challenge, the ball ends up in the net and a goal is given with Stekelenburg having the misfortune of being credited with an own-goal. But was the 'keeper fouled?
DERMOT'S VERDICT: WRONG DECISION
DERMOT SAYS: I don't think many referees would have given this goal. The reason Stekelenburg drops the ball is because Negredo headers his arm. It's gone down as an own-goal, so it proves the forward has not headed the ball.
MATCH: Watford v Manchester United, Premier League, Sunday
INCIDENT: Anthony Martial is substituted nine minutes after a clash of heads with Watford's Daryl Janmaat - he had immediately received treatment but was allowed to continue.
SCENARIO: The France attacker was treated on the pitch for two minutes before being led away. However, he was allowed to continue. Martial played on for another five minutes before he was dispossessed in the build-up to Watford's opening goal, his head making contact with the ground as he fell. He was substituted nine minutes after the original collision.
The Premier League introduced a new rule regarding head collisions two seasons ago, making substitution mandatory for any player deemed by medical staff to be concussed on the field. Should the referee have stepped in?
DERMOT'S VERDICT: UP TO THE MEDICS
DERMOT SAYS: In terms of the referee's involvement in these types of incidents, they're taken out of the equation, which is a good thing.
This happened after the Hugo Lloris-Romelu Lukaku incident a few years ago and now the doctor assesses the player and makes the judgement. The two medics came on, reviewed it and decided he was was fit to play - it's at that point the referee has to take their word for it. The referees are not medically equipped - it's the best way as referees have no knowledge about that type of injury.
MATCH: Manchester City v Bournemouth, Premier League, Saturday
INCIDENT: With the game at 4-0, Man City forward Nolito and Bournemouth defender Adam Smith engage in a touchline tussle, which ends with Nolito pushing his head into Smith as the pair squared up.
SCENARIO: Nolito was sent off for violent conduct.
DERMOT'S VERDICT: CORRECT DECISION
DERMOT SAYS: I think the referee has done really well here. Instead of brandishing a red card in front of all the players, he takes the player away towards the tunnel and gets the red card out. It's really good practice.
MATCH: Tottenham v Sunderland, Premier League, Saturday
INCIDENT: Sunderland defender Patrick van Aanholt was originally selected to play by David Moyes, but 15 minutes before kick-off, he was informed by a team-mate in the warm-up that he was dropped, much to his surprise.
SCENARIO: When pressed on the mystery after the full-time whistle, Moyes did not explain what the "medical reasons" were for Van Aanholt's withdrawal and the Dutchman refused to speak to the press in the mixed zone. What is the referee's protocol?
DERMOT'S VERDICT: DOCTOR'S CALL
DERMOT SAYS: Basically, the doctor has said to the referee that Van Aanholt is not fit to play. If the doctor signs a certificate to say he's not fit to play, then the manager is free to replace the player and bring in another player as a substitute. It's all down to the doctor.
MATCH: Inverness CT v Celtic, Scottish Premier League, Saturday
INCIDENT: Inverness were denied a penalty after Ross Draper was bundled over by Erik Sviatchenko in the 18-yard box, with referee Don Robertson waving away their vociferous appeals.
SCENARIO: The game at the time was locked at 1-1, but soon after the incident, Celtic counter-attacked and took the lead through Scott Sinclair.
DERMOT'S VERDICT: WRONG DECISION
DERMOT SAYS: This is an error of judgement from the referee. I think it's a foul and a red card - there's no doubt there's serious contact. The defender doesn't win the ball because it's too far in front of him. I think it's a wrong call.