It was tough on Malcolm O'Kelly yesterday. The veteran of 60 caps is now required to be tough back. O'Kelly's form may have dipped, but amid the general sympathy for him yesterday there was also a frisson of excitement around the City West Hotel about Donncha O'Callaghan's arrival to the forefront of Eddie O'Sullivan's game plan.

It's not that he hasn't been here before, but his elevation to the starting XV to join his Munster second-row partner Paul O'Connell has been widely welcomed - not least because the pair will service a back line freshly boosted by the twin creative potential of Brian O'Driscoll and Gordon D'Arcy.

With just eight caps, all as a replacement, O'Callaghan has three days to think of his first start in Lansdowne Road. In recent times his rampaging has usually been done in tandem with O'Connell, and with Munster the pair have been a huge success. The step-up in levels will be a test of the engine's calibre under higher revs and greater stress.

"Donncha came on last week and did well. He plays with abandon," said O'Sullivan. "He throws his body around the place. He did a good job at the World Cup for us and he's been breathing down Mal's back now for a while. I think starting him will bring another edge to it. Tough call, but he will spice it up."

O'Callaghan first dipped his toes into international waters in the corresponding game against Wales last season and found the temperature manageable. Ireland won the match but only just.

Since then he has steadily worked his way into the selectors' eye-line with step-on cameo roles, his marauding style typically effective and engaging.

"Starting? Oh yes, it is a different psychology," he says. "You've all this time to think about it. You can probably play the game 100 times in your head if you let yourself, whereas when you're subbing you're just in the thick of it straightaway and you don't even think about it. Yeah, it is different.

"You're always a bit surprised (when selected) but you're always a bit anxious too, because I suppose when you're going into team meetings you're always hoping there's a call-up for you.

"It's just not my way of thinking that you just go in there (team announcements) and fill up the numbers. Since I've been up here I've been looking to push for a start.

"I was glad to get on (last week) for a bit more time than I'd been getting. Before that I'd been getting a few minutes every now and then, which I suppose was good for blooding me. I was happy with some of last week but I was disappointed that they scored one of their tries and we didn't get one given the amount of possession we had in their territory."

The news of his elevation came as a surprise to the Cork Constitution player, but you suspect this natural swashbuckler, who was steeped in rugby long before starring on the Irish under-19 team that won the FIRA World Cup, will take some dislodging from the jersey.

"Mal has set the benchmark for Irish second rows in the professional era. He's come on and he's driven it," says O'Callaghan. "To be honest I'm a bit overawed to be putting on the man's jersey because I've so much respect for him. He was the first person up to me to wish me luck. That must have been very hard. I appreciated it so much coming from the fella."

As with O'Kelly, there's an honesty about O'Callaghan, not just in the way he plays his rugby but also in the expression of his views. Asked whether having O'Connell riding shotgun is a particular help, he doesn't hesitate: "It is and it isn't. I think we do complement each other but there's so much pressure for places that you have to go out and perform for yourself. It's great to have Paul but I'll just worry about my own personal performance on Sunday."

O'Sullivan's declared philosophy for the match was to pick a team to play the best game for Ireland. With reruns of Wales's game against Scotland still likely to be whirring inside his perfectionist's head, the coach clearly saw O'Callaghan's ability not just in lineouts but also around the park as crucial.

"I'll just go out and play my own game. What I do with Munster and Cork Con is pretty much what I do. That's all I have to offer. Nothing more than my average game," says O'Callaghan.

That should do nicely.