Murray cool ahead of Italy clash
The British and Irish Lions scrum-half is "through that first contact fear" after a month out with neck trouble, and should start against the Azzurri in Rome.
The sharp tactician shoulders the brunt of the playmaking duties in a French-style half-back set-up at Munster, but does not expect a repeat at Test level this weekend.
"There's no more pressure than usual," said Murray of conducting Ireland's tempo in Sexton's absence.
"Other people might say there is but I don't see that.
"It's come up with Munster before that there might be a bit more pressure on me but I just try and play my own game, try and play well and if I play well hopefully all that stuff, that pressure and responsibility, looks after itself.
"The two lads, the two Ians who are going for the 10 spot this weekend, have been in and out of the team in training.
"They have been getting their reps in and doing real well and I have no issue with whoever gets picked. "
Forwards coach Simon Easterby confirmed fit-again flanker Sean O'Brien is "in the mix" for selection following his strong showing for Ireland Wolfhounds on Friday night.
The abrasive Leinster back-rower has endured two reconstructions on the same shoulder in 14 months, but is now primed for his first Test action since November 2013.
"Sean was good on Friday night, in his own assessment he blew up a little bit and you would do," said Easterby.
"He's a long time out of the game but we all saw what he can be, the competitiveness of the man.
"Certainly having him in the mix for selection is a real positive, especially after losing Chris Henry and Rhys Ruddock after the autumn.
"Obviously Rhys broke his arm and Chris has had his illness, so we've had a few players step through, but having Sean come back to full fitness and back into the squad and in the mix is great to have him as a selection option."
Jamie Heaslip remained a fitness doubt on Tuesday with shoulder trouble, but Easterby said the Leinster number eight still has time to prove his fitness.
"Players might not train until a Tuesday, that's not unusual," said Easterby.
"You have to adapt and give players opportunity, without it affecting preparation."
Boss Joe Schmidt will be relieved to have frontline nine Murray fit to start in Rome, with the increasingly-poised half-back crucial to Ireland's tactical nous.
Murray's ability to run a game in the manner of a fly-half from the nine berth could prove priceless at the Stadio Olimpico, especially in the absence of Racing Metro 10 Sexton.
Murray said he has eased comfortably back into confrontational training, claiming there is "no hassle" now over the disc problem that has blighted his last month.
"I just over-extended my neck against Zebre about a month ago," said Murray.
"I maybe could have got back for the two European games, but the specialists and doctors advised against it.
"I'm feeling good and fit to play now.
"It was a disc problem in my neck. It's gone now. There is no hassle over it.
"I just ran into a player's chest and squashed myself. It wasn't the smartest idea - I won't be doing that again!
"I have done all my contact. I have done bag work, tackled a few of the lads and feel good. I've gotten through that first contact fear if you want to call it that."