LEINSTER SAY JOHNNY Sexton did not suffer concussion during Leinster’s heavy defeat to Wasps on Saturday.

Leo Cullen has stated that Sexton passed his Head Injury Assessment (HIA) but the province’s medical staff weren’t happy for him to return to the field.

The Ireland international, who was making his 100th start for the province, clashed heads with former Leinster centre Brendan Macken during the first-half of the 51-10 Champions Cup loss at the Ricoh Arena.

Sexton did not return following his HIA, with debutant out-half Cathal Marsh taking his place for the remainder of the game.

Speaking after the game, Leinster head coach Leo Cullen said Sexton had failed his HIA, while the province’s official Twitter account also tweeted that the out-half had failed the HIA.

However, Cullen said this afternoon that Sexton had passed the HIA, but added that the province’s doctor wasn’t 100% satisfied to send Sexton back into the game.

“He clashed head with Brendan Macken early in the game after about eight minutes and went off and did his HIA assessment, passed his questionnaire fine and was ready to come back out but the docs just erred on the side of precaution,” Cullen said this afternoon.

“They weren’t 100% happy so made the call at that stage so he did not return.”

When asked to clarify if Sexton had in fact passed his HIA, Cullen said: “Yes he passed his HIA assessment, yeah.”

Sexton, who has had a history of head injuries after sustaining four concussions in 2014, is now under the care of the Ireland medical team as Joe Schmidt’s side begin preparations for the Six Nations today.

The extended squad assemble in Carton House later and Cullen is confident Sexton will be fit for the opening game of the campaign against Wales on 7 February.

“He’s obviously in camp so he will be managed with the Irish management at this stage and he’ll follow those return to play protocols,” Cullen continued at Leinster’s HQ in UCD.

“Yeah, I would imagine so,” he said when asked would Sexton be available for next month.

Sexton leaves the field alongside Leinster's doctor. Source: James Crombie/INPHO

“Originally he was due to come back on and they just erred on the side of precaution. We lost Kevin McLaughlin earlier this year to concussion basically but Johnny’s is not concussion, it’s a head knock so it’s slightly different.

“We’re always ultra cautious with the recent history of our players, even the way we’ve handled Sean O’Brien and making sure those guys get the best treatment.

“You’ll always err on the side of precaution with guys who have had those bangs in the past.”

As the inquest into Leinster’s biggest European defeat began in earnest this morning, Cullen has been left to work with a reduced group as he faces the reality of missing 35 players for Friday’s game against Newport Gwent Dragons.

Marty Moore will now miss Ireland’s Six Nations title defence after he sustained a grade two hamstring tear in Coventry at the weekend. The prop will be sidelined for six to eight weeks.