Warren Gatland has told his British and Irish Lions to prepare for a "cup final" after their 27-9 defeat by South Africa in the second Test set up a series decider next Saturday.

The Lions entered half-time at Cape Town Stadium 9-6 ahead through three Dan Biggar penalties but the match then turned on its head, with the world champions taking control up-front and in the air.

Makazole Mapimpi and Lukhanyo Am crossed in the third quarter while the boot of Handre Pollard did the rest, setting up a winner-takes-all scenario in the climax to the tour.

"The players are very disappointed but next Saturday is a cup final. That's how we've got to look at it and prepare," head coach Gatland said.

"There are a few things we've got to tidy up. It's 1-1 and South Africa put a huge amount of emotion into that game. We've got that chance next week to hopefully take the series.

"We were happy at half-time and in the second half just didn't get into it. We got no momentum, no real opportunity to play. Nothing at all from our kick returns and that was disappointing.

"They scrummaged well in the second half and got some reward from that. We felt going into half-time that we'd carried well, we had some forward momentum and we just didn't achieve that at all in the second half."

The build-up to the second Test saw South Africa director of rugby Rassie Erasmus release online an hour-long video critiquing the performance of the officials at Cape Town Stadium a week earlier.

Warren Gatland speaking with Rassie Erasmus after the first Test

The Springboks then doubled down on their claim of being disrespected by the officials and accused Gatland of "destroying the dignity of the series" after the Lions made it known that they felt Marius Jonker - a South African - should not have been TMO.

"I thought it (Erasmus' video) was pretty interesting. I won't be going on social media this week," Gatland said.

"I don't really want to comment on that because I want other people to take care of it. The last thing we need is a war of words and being accused of doing certain things.

"It's amazing to me how the narrative changed with regard to the TMO. I didn't make one comment leading up to the game last weekend about the TMO yet I was accused of questioning his integrity.

"That was the message they were sending out. We'll keep things to ourselves and keep to the proper channels.

"We've got systems and process in place. Hopefully World Rugby looks at that to make sure everyone follows the protocols.

"We deal with the referees through World Rugby. That's the process. I just hope it doesn't get to the situation where we end up with things on Twitter and people airing their views in that way and not through the proper channels.

"I found it quite strange that that approach was taken. It's definitely not something I'll get involved with. It's important that we keep up the integrity of the game as much as we can."

Cheslin Kolbe escaped a red card for taking Lions scrum-half Conor Murray out in the air.

"We'll have our meeting with the referee this week and see what the assessors come back with in terms of their decision. It didn't look great from where I was but he decided it was a yellow card decision," Gatland said.

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