Ireland are sweating on the fitness of Rory Best for Saturday’s Test with South Africa, but Jonny Sexton is expected to be fit.
Ulster hooker Best is struggling with a calf problem and Ireland team manager Michael Kearney says it is “difficult to say” if he will face the Springboks.
Head coach Joe Schmidt will be desperate for Best to be fit for the Aviva Stadium contest given Ireland's raft of front-row injuries.
Best went through "modified work" in training on Monday, with his progress to be monitored throughout the week.
Ireland must face South Africa without props Cian Healy, Marty Moore and Nathan White, while Mike Ross is still fighting for fitness after groin trouble.
"Rory Best has a tight calf that will be monitored all week," said Kearney. "He will go through modified work today (Monday) and will be monitored as the week goes on.
"It's probably a little bit more difficult to say with Rory, but he will do modified work and be monitored closely.
"Mike Ross went through some running and multi-directional work as well as static team work on Friday, and will be introduced to full training over the next few days.
"He will be closely monitored but the prognosis is positive and we are reasonably confident he will be available for selection."
Available
Sexton is expected to train fully all week despite suffering "tightness in his thigh" during Racing Metro’s home defeat to Oyonnax last Saturday, with Kearney confirming the Top 14 side agreed to limit his involvement to 40 minutes.
Gordon D'Arcy, Rob Kearney and Jack McGrath are all expected back in full training this week, while Stuart Olding and Tommy Bowe have come successfully through concussion protocols and will be available too.
"We don't have a concern over Jonny,” said Kearney. “He will be expected to play a full part in the sessions over the week.
"It had been pre-arranged that he would come off at the weekend; he was always going to play a limited part in the Racing game."
Meanwhile, British and Irish Lions scrum-half Conor Murray has urged centres Robbie Henshaw and Jared Payne not to become "bogged down" by following Brian O'Driscoll into Ireland's No 13 shirt.
Kiwi boss Schmidt has confirmed Connacht's Henshaw and Ulster's Payne will battle it out to replace the now-retired O'Driscoll at outside centre.
Team manager Kearney said there had been no IRFU talk of retiring the 13 shirt in a USA sport-style gesture of respect to O'Driscoll.
Opportunities
"There's been much talk of it, we had all that chat last year throughout the whole season, the long farewell," said Murray.
"We're pretty much used to that now and there are opportunities for lads to fill into that famous jersey.
"There will be pressure on them, but they're going to have to be their own men, and not be too bogged down by the title of that jersey.
"It's something the public will talk about but within our squad we know the players we've got and what we're trying to do.
"So we're not going to dwell on that too much.
"I think they see it as an opportunity, they are two really good players and they bring a lot of different things to the table.
"They will be hugely influential if they do get a chance in there.
"They are going well in training, swapping in and out, so it's up to Joe who he gives the shirt to, but whoever gets it, I'm sure they'll do a great job."
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