Ulster coach Dan McFarland was left unhappy over a tackle which led to Marcell Coetzee's early departure from Friday's 35-3 Pro14 win over Connacht.
Coetzee was injured in a clash of heads with Connacht's former Ulster prop Paddy McAllister in the move which led to a superb try from Billy Burns.
Further attrition from the win was an ankle injury sustained by Louis Ludik.
"We lost a big player [Coetzee] for us and nothing comes of it," said the Ulster coach.
McFarland pointedly compared McAllister's tackle to the incident involving Will Addison in the European Champions Cup win over Clermont Auvergne in November which led to the Ireland back receiving a four-week ban.
"Will Addison was back after a four-week ban and one of the first things he has to watch is a tackle that was way worse than his - way worse - that ends in nothing."
Coetzee was able to walk off following what appeared to be a no-arms tackle by McAllister but didn't come back on after undergoing a head injury assessment in a contest watched by a full house at Kingspan Stadium.
McFarland said that he didn't have any more information on Coetzee's knock but did say that Ludik's ankle injury which forced him off moments later "didn't look great".
Speaking on Twitter on Saturday morning, McAllister insisted that there was "zero intent in the head clash and those who think otherwise don't know me".
While delighted with Ulster's win as they repelled intense Connacht pressure while down to 14 men late in the first half before adding three second-half tries to complete a dominant success, McFarland did refer to some line-out difficulties which Connacht were unable to exploit.
"We will go back and look at that. We'll have to solve it but we will. I have no doubt about that."
Ulster's next game sees them hosting Munster on 3 January and McFarland says his side will have to improve from the Connacht display to compete with Johann van Graan's side in their final Pro14 contest before the European games against Clermont and Bath.
"Munster are going to come here very strong. It seems like we've got three Champions Cup-level games coming up which is pretty exciting for the crowd and for us.
"It will be a real test. I genuinely feel we will have to improve a fair bit if we are going to beat Munster next week."