England & Harlequins prop is facing a nervous wait for the verdict on a potential charge after being accused of eye-gouging during the 30-22 loss to Northampton on Saturday.
The incident involved Sinckler and Northampton`s Michael Paterson. The action happened in the 49th minute when it is claimed that the England international made contact with Lock's right eye during a ruck.
After viewing several different replays the video referee could not make a conclusive decision and Northampton were awarded just a penalty for Sinckler taking Paterson's scrum-cap off.
The incident was brought to the attention of the referee by Paterson, who claimed Sinckler had "100%" made contact with his eye - scroll down to see the incident.
The prop has been backed by Harlequins director of rugby John Kingston who defended Sinckler and then accused Northampton of foul play themselves after Dave Ward was left with a black eye.
"Unequivocally, it was not a gouge,” Kingston said. "Absolutely not. Kyle said he made contact with is gear. He can't do that."
“I know how it [Ward's black eye] happened because he's told me and I believe him,” Kingston said. “I'm pretty disappointed about that. He's not happy about it.”
Should Sinkler be found guilty, he could receive a minimum suspension of 12 weeks.
The final decision will be made by citing commissioner Chris Catling, with his answer expected in the next 48 hours.
A similar incident happened with Chris Ashton two seasons ago. The Saracens player was banned for 10 weeks after connecting with the eyes of Ulster's Luke Marshall - even though the contact appeared to be accidental.
What do you think? Does the footage provide enough evidence to suggest Sinckler should be suspended? Let us know in the comments below.