But Lions flanker O’Brien said: “I know ’Cheiks’ very well with him being at Leinster.

“He is an animated character as well, so I am sure he will have them fired up and wanting to be really aggressive and come hard at us.

“We are getting closer and closer to the Test games, and teams are going to try and come at us a little bit harder. The Waratahs will be no different.

“It’s going to be a very tough game, and whatever side is picked for the Lions we are going to have our hands full at the start of the game again.

“They are really going to come at us out of the blocks and try and hurt us a little bit, so it’s going to be massively intense again.”

The Lions travelled by road two hours down the coast from Newcastle – scene of yesterday’s 64-0 victory over a Combined Country XV – today to Sydney, where they were greeted by leaden skies and pouring rain.

Head coach Warren Gatland will name his starting line-up for the Waratahs encounter tomorrow.

Some previous Lions coaches have used the final Saturday game before the first international to give the probable Test side a run-out, but it is not thought Gatland will go entirely down that route.

The back-row and second-row combinations remain fiercely contested, although his potential Test threequarter line of Alex Cuthbert, Brian O’Driscoll, Jamie Roberts and George North all played yesterday.

Asked if he expected the Test team to feature this weekend, O’Brien added: “Your guess is as good as mine. I don’t think so, but who knows?

“Every week you could say is this the Test team? But it is all up in the air in every position, and we are just trying to do our own jobs and keep the head down and the coaches will pick the Test side when it comes to it.

“It’s getting towards the business end of it, and it is exciting.”

O’Brien could find himself in the Test back-row mix, although a bench role looks more likely, given his ability to cover both flanker roles and number eight.

He featured at blindside against the Country XV, with in-form Welshman Justin Tipuric wearing the number seven shirt, and O’Brien can realistically expect one more outing before the Test team is unveiled.

“I dropped a ball in the second half in their 22, but other than that I was happy enough,” he said, reflecting on his performance.

“I did what I had to do, job-wise, and kept working to the very end.

“We made life difficult at times for ourselves in the second half. There were a couple of errors, we were a bit sloppy and we went away from the game-plan.

“We’ve set ourselves standards over the last couple of weeks, and we have to maintain those. There is stuff to work on, but that is the case every week.”