Joey Carbery has admitted that he feared for his World Cup prospects in the immediate aftermath of injuring his ankle against Italy.
The Ireland back-up out-half left the field on a medical cart in the second half of the 24 August friendly win in Dublin.
The Munster man has only returned to full training this week but is now on track to make the match-day 23 for Sunday's Pool A clash with Scotland in Yokohama.
The 23-year-old said: "The ankle is feeling pretty good. I'm happy, there was a couple of nervous days [after] the injury happened.
"I'm happy just to be here and the ankle is kind of healing so I’m pretty happy with it all.
"Within myself I was like, 'Will I be ready, will I be able to go?’ but I had great help from the physios and the doctors, they got me through it all. There was a lot of long days but it’s worth it all in the end.
"It’s hard when you are not training to keep up with the rugby stuff so I just tried to pay attention in meetings, keep on top of everything so when I came back training it wouldn’t be a shock to me."
Primarily used as a back-up to Johnny Sexton, Carbery can also play at full-back and is the squad's cover for the scrum-half position in the event of injuries to Conor Murray and Luke McGrath, despite last playing in that position at "under-18" level.
Concern over Rob Kearney's calf injury has also prompted suggestions he could slot in at 15, while talk about sitting at first centre, in a Ford-Farrell arrangement is purely external, he says.
"I’ve only been in around 10," he explained when asked about what training patterns he had been running.
"I haven’t had too much time other than this week to do anything. Hopefully, over the next couple of weeks I’ll get in a few other positions.
"I don’t mind, I suppose it adds another string to my bow.
"I haven’t been approached by the coaches about [the 10-12 option] so until I hear it from them I won’t look into it too much.
"I’d be more than happy to give it a go but it’s the guys in charge who would be picking that."
Meanwhile, Sean Cronin believes he reacted in the right way having lost his place in the squad during the ill-fated spring campaign.
The hooker, who has 70 Ireland caps, said: "Obviously in the Six Nations I got dropped from the squad but I think it shows that I have good mental strength because I fought to get back in, had good form at Leinster.
"All you can do, when things don't go your way, is see what you can do better and just be positive. I was pretty happy that I could make it.
"This is my third World Cup so I've been sniffing around for a while."
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