Mako Vunipola and Owen Farrell are named among the replacements for the British & Irish Lions' first test against Australia on Saturday.

It was thought by many that Vunipola might start the match after impressing in warm-up matches but head coach Warren Gatland has opted for Alex Corbisiero at prop instead.

Gatland suggested weather conditions, the referee and Vunipola's scrumming were all factors in his decision.

"Mako's pretty unlucky. We've looked at the weather conditions and there's potentially a threat of showers," said Gatland.

"No doubt [Australia coach] Robbie Deans has looked at Mako technically at scrum time.

"Mako coming off the bench will give us a huge amount of impetus and we think that will be a big strength.

"Technically, we think Alex is probably a little bit sounder and with the referee [Chris Pollock] at scrum time, we think we have potentially got a little bit of an edge.

"Alex is also perhaps a bit more of a combination with Tom Youngs and Adam Jones. There's no doubt Mako is very unlucky but he will make a big impact off the bench."

Farrell is also among the replacements after Jonny Sexton was selected at fly-half. Matt Stevens and Brad Barritt, who have both featured in warm-up games, miss out.