MAGNERS LEAGUE:THE ESTABLISHED Leinster galacticos, and the young tyros in their backline, are moving into new territory. The arrival of Isa Nacewa, and his ability to play in any position from outhalf to fullback as well as take place kicks, has possibly contrived to put them all on edge; which, of course, is no doubt what Michael Cheika was hoping to achieve.

Jonathan Sexton is a prime case in point. Last season, carefully developed by Cheika and David Knox, he made tremendous strides and despite being Felipe Contepomi's understudy, actually started 13 Magners League games (11 more than the previous season) while effectively becoming Ireland's third-choice outhalf as the starting number 10 in the Churchill Cup.

This season, though, in addition to the Argentinian outhalf Felipe Contepomi, there is Nacewa as an alternative number 10 - the position he moved effectively to in two of the pre-season games and last Saturday in Cardiff.

As Sexton noted yesterday: "In some ways it's going to be as hard for me to get into this backline as it is trying to get into the international set-up. There's three outhalves here and then at the moment (with Ireland) there's O'Gara and Wallace and then the rest of the young lads trying to catch those two."

That said, he maintained that "competition is good", adding: "It's going to improve everyone and it means it's going to keep everyone on their toes. Isa's come in and kept everyone going - he can play anywhere across the backline. So it's going to be good for me if I respond in the right way to it. I just have to keep improving and I'm sure I'll keep getting the chance if I do that."

Nacewa has made a good impression already on everyone, including Sexton.

"He's a really good guy. He's a really hard worker and has a good knowledge of the game. He's really good. He's brought a lot to the squad. In terms of his ideas, he's played under the new laws so he's brought a lot.

"He's a good player, he's performed well and no one could have any questions over him being in the team or in the squad."

Sexton wouldn't have been alone in noticing that they were two highly decorated Irish internationals on the bench last week.

"You see Luke (Fitzgerald) and Girv (Dempsey) on the bench and you think 'I've got to play well to be in the team next week'. It's tough in a way. And then you've got Gordon D'Arcy who is not even there at the moment. It is huge competition but squads win trophies. That's why we won the Celtic League last year because there were guys that could come in and do well, but then we fell short in the Heineken because maybe our squad was maybe a little bit short."

He has also rationalized this season's 'rotation' policy, at least until the first selection for the Heineken Cup away to Edinburgh after the first block of five league games.

"So we won't know what his first-choice team will be until then so we're just going to have to train well and take our chances in the games."

Nevertheless, the pressure to make the most of one's chances is therefore also more acute, as evidenced in Sexton's apparent frustration with an opening night performance which he described as "rusty" and left Leinster requiring "a bit of improvement" in their first competitive home game of the season against Edinburgh on Friday, especially with the ball.

While coach and players were unhappy with their use of the ball, there was an encouraging flip side to that coin.

"Maybe we could have used the ball a little bit more, which we looked at afterwards but, again, we came away with the result not playing particularly well - maybe something that Leinster teams in the past might not have done."

Sexton is a rare specialist among the abundant versatility of so many Leinster backs, which effectively gives them three choices at outhalf and four at full-back, not to mention hosts of options on the wings and at least three in midfield. Yet the relative lack of settled combinations is not a concern for defensive coach Kurt McQuilkin.

"It's probably better from a defensive point of view having everyone rotate and being quite comfortable with what we're doing. Once we've got our pattern and our formation right, whoever comes in or out doesn't create a big problem, because they're all au fait with what their roles and responsibilities within set piece defence and phase, so it doesn't really rattle us defensively who comes in or who goes out," he said.

While Fitzgerald had to be content with a place on the bench, Rob Kearney was moved to the wing to accommodate Nacewa's inclusion after his eye-catching displays at fullback on the summer tour in New Zealand and Australia. McQuilkin envisages Kearney having a few runs there and argued that "with the modern game - whether you playing on the wing or fullback - it's really a back three scenario so you all basically play that same role.

"Everyone's going to get a run in different positions because we have so much depth there, so it's a case of everyone biding their time and filling in when they can. But I must admit the attitude of all the players - and we've got some pretty big-game players - they all just want to get on the pitch and show their wares, which is good to see."

McQuilkin was unhappy with Leinster's first-up tackling against Cardiff, which he feels is a particularly pertinent area against Friday's opponents.

"With Edinburgh you've got to make your first-up tackles, and you're looking for a very dominant tackle situation. If you start soaking with them and they get in behind you and they just rush through the holes looking to link up and support.

"We're looking to initially 'D-up' very well early on and set a platform, and then let our attack take over from there, and I guess just being very patient in attack."