British and Irish Lions 2017: Gatland's 'brain explosion' warning for Williams

Liam Williams (obscured) was sin-binned against Blues for a second illegal tackle

British and Irish Lions coach Warren Gatland hopes Liam Williams avoids a "brain explosion" in the first Test against New Zealand on Saturday.

Wales' Williams was a surprise inclusion to start at full-back for the first Test.

The ex-Scarlet was sin-binned on his Lions debut against the Blues

"You know that every now and then there might be a brain explosion with Liam Williams, as we saw with the yellow card," said Gatland.

"He must be switched on, mentally."

Saracens-bound Williams impressed on Tuesday as the Lions beat the Chiefs, but Gatland noted another mistake in that game.

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"To be honest, he has played his way into the Test team by his performance," Gatland added.

"He did one dumb thing, which was his little chip ahead."

However, Gatland said Williams has showed the All Blacks he is a threat during Wales' tour there in June, 2016.

Gatland added: "He caused the All Blacks problems with his running and attacking game, and when we sat down on Wednesday we asked whether we needed to look at our back-three.

"We needed to go there and have players who have some footwork and to play some rugby."

How Daly got the nod over North

Another Welshman, George North, lost out to England's Elliott Daly for a wing spot.

Gatland said: "Elliot Daly was outstanding (against the Chiefs). That run down the sideline, where he threw the inside pass, there aren't many who can do that.

"He just put the gas on and passed inside.

"Elliot is just an outstanding rugby player. You tell him once and he gets it. There are not many people who understand the game as well as he does."

Lock Jones 'under pressure' from Itoje

Maro Itoje (L) is on his first Lions tour and Alun Wyn Jones (R) his third

North starred for the Lions against Australia in 2013 as did fellow countryman Alun Wyn Jones against the Wallabies and four years earlier in South Africa.

But Gatland says Jones is "under pressure" from replacement Maro Itoje, who lost out to Jones on the "toss of a coin".

"That was a tough call. Alun Wyn played well against the Crusaders, Maro was outstanding against the Maori," said Gatland.

Davies braced for Test 'intensity'

Wales centre Jonathan Davies is braced for the "pressure" and "intensity" of the Test series.

Saturday's first Test will be the Welshman's fourth consecutive Lions Test start.

Davies, 29 started all three Tests in the series win in Australia in 2013 but expects a tougher task this time.

"I think some sort of familiarity helps but the game's moved on since the last tour," he said.

"The pressure and the intensity has gone up a lot of levels.

"The first Test of a Lions series in New Zealand, I don't think they get much bigger than this."

Scarlets' Davies is one of four Welshmen in the starting XV to face the World champions at Eden Park in Auckland, where the All Blacks have not lost since 1994.

Williams, number eight Taulupe Faletau and Jones all start, but tour captain Sam Warburton is on the bench alongside hooker Ken Owens, full-back Leigh Halfpenny and scrum-half Rhys Webb.