The incident is alleged to have taken place during a ruck in the 64th minute of the Lions' 27-9 loss at Cape Town Stadium on Saturday.

Sinckler, who has a chequered disciplinary record, will be hit with a minimum 12-week ban if the citing is upheld by Tuesday's disciplinary hearing.

Remarkably, no other player has been cited from a fractious clash, despite numerous flashpoints.

Earlier on Sunday, the Lions issued a statement on behalf of Stuart Hogg in which the Scotland full-back denied his own biting incident involving opposite number Willie Le Roux.

Hogg's head made contact with the left arm of Le Roux when tempers flared in the second half with footage and stills of the incident going viral on social media, but the Scot has been cleared of wrongdoing.

"Following speculation that has surfaced online, I would like to categorically deny any foul play in last night's game," Hogg said in the statement.

"I would never bite an opponent and I am annoyed and upset by this unsubstantiated accusation. I've always been proud of playing rugby in the spirit of the game.

"Respect to the Springboks for their deserved win yesterday. The squad is hurting after last night's defeat, but it's all to play for next week. It's going to be a cup final and everyone's going to be up for it."

Yet Sinckler faces an anxious wait, knowing biting is treated severely by rugby's judiciary and carries a low-end sanction of a 12-week ban, rising to in-excess of 24 weeks for severe offences. The maximum length of suspension is 208 weeks.

The England prop, who was a second-half replacement for Tadhg Furlong, can expect little mitigation if the biting incident is proven because of his previous misdemeanours.

In January he was suspended for two weeks for swearing at a referee and four years ago he received a seven-week ban for gouging.

Putting to one side the disciplinary fallout from the penultimate match of the tour, coach Warren Gatland must pick his Lions up from their heaviest defeat since the disastrous 2005 visit to New Zealand.

The Lions toiled up front and their back three were vulnerable to the aerial bombardment they knew was coming, so changes appear inevitable.

"We'll spend the next couple of days reviewing the game and then looking at what we think is the best 23 to put out," Gatland said.

Australian Associated Press