Line-out coach Paul O'Connell says Ireland will be facing the best Scottish side of his career as a player or coach this Sunday. 

Scotland lie fifth in the Six Nations table following a second round loss to Wales, and a postponed game away to France.

Ireland's performances in the opening two weekends drew plenty of criticism, but the two losing bonus points they accrued from those defeat to Wales and France have been augmented by a five-point haul from Rome.

With the squad again approaching full fitness - save that of Josh van der Flier (return-to-play protocols) - there's renewed optimism that Ireland can end the campaign on something of a high, starting with Sunday's game at Murrayfield.

Ireland have wont he last five meetings of the sides, including a 31-16 victory in the Autumn Nations Cup.

But from O'Connell, there's a sense that the tide is turning.

"It's the best Scottish team I've ever gone up against - as a coach or a player," he told Tuesday's press conference, "They're very well-coached, very physical, and they've got some real x-factor players as well - Finn Russell just to name one, and Stuart Hogg to name another.

"I think they're in a very very good place and we're aware of the challenge.

"We've taken confidence from some of the things we've done in the last three games. We've probably been unlucky in some regards, and we haven't helped ourselves in other regards.

"We've probably given sides a leg-up when we've played them at times, and that's something we just can't do going forward in the next two weeks.

"You have to be hard to beat. You can't give things away to teams, and unfortunately we've done that a little bit.

"In the next two weeks, that's probably one of the most important parts of what we have to deliver. We have to be hard to beat.

"We can't give things away, we can't give teams a leg-up because this Scottish team will take advantage of that."

As far as Scotland are concerned, for O'Connell it's a case of black cat, black kitten as the influence of the coach pervades the team.

"I think any team that's coached by Gregor Townsend always attacks really well," the former Ireland captain said.

"And going back to his Glasgow days, they always have an incredibly physical edge.

"You think sometimes if a coach is into attack, his teams won't have a physical edge but every single Glasgow team I played back in the day were excellent attacking sides, but they were physical as well.

"And it's the same with this Scottish team now. So much of the good attack in the Autumn Nations [Cup], and in the start of the Six Nations has come from Scotland.

"And then they're very very physical as well. It was a fantastic performance by them against England in the first game - excellent set-piece performance which laid a real solid foundation for them to go on and win.

"So it's a massive test. These next two weeks - against a resurgent, confident Scottish side and an English side that we've struggled against in recent months and years - it's a real tough challenge."

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