And the Wales star says he has taken none of his half century of appearances for granted, after suffering a career-threatening knee injury early on in his career.
After celebrating Grand Slam glory in 2005 he had a recurrence of a knee injury whilst touring with the British Lions that summer and for a second time feared his rugby playing days were over.
But the man they call ‘Mr Reliable’ is back with avengance and faces the Azzurri now seemingly an integral part of new Coach Warren Gatland’s plans.
”It will probably be the proudest day of my career,” said Shanklin, who is set to lead the team out at the Millennium Stadium this afternoon.
”When I was injured I did not know how many more caps I would win, if any. You don’t know when your last game is going to be.
”I have been careful in training all week to make sure I get to run out tomorrow.
”It is nice to get 50 caps but it is even better if you get to that landmark at home, so it has worked out well.”
Shanklin grew up in London and began his professional career in the Premiership with Saracens – but Wales was always his international future.
His father, Jim, won four caps for Wales between 1970 and 1973, and Shanklin’s Test debut came in Japan on the summer tour of 2001.
He has now played for seven Wales coaches and found himself having to prove his class on each occasion. Again, he always succeeded.
Even Warren Gatland started his tenure by leaving Shanklin on the bench, although his impact in the second half of Wales’s victory over England at Twickenham quickly convinced the New Zealander otherwise.
Shanklin and Gavin Henson are now back in tandem in the Welsh midfield for the first time since the 2005 Grand Slam.
Is it like old times?
”It is a bit. I struggled to get into the game against Scotland, but Gavin showed some lovely touches,” said Shanklin. ”I have been working hard on my angles and I hope to run off Gavin a bit this week. I hope we will work more of a partnership this week.”
The Henson-Shanklin centre partnership is not the only echo of 2005 in the current Welsh set-up. In that grand slam year, Wales also opened with a battling win over England before growing in confidence through the tournament.
Wales began this year’s campaign – and the new Gatland regime – by snatching victory at Twickenham before eventually seeing off a dogged Scotland side a fortnight ago.
”We have won both games but we haven’t played to our peak yet,” said Shanklin. ”We know there is more to come, which is pleasing.
”In 2005 we got better with each game and we finished the last two-and-a-half games playing the best we have played for a while. There is that feeling.”
But Wales know better than most how tough Italy are, having not beaten them since the grand slam.
The Azzurri drew that 2006 game 18-18 and then beat Wales 23-20 in Rome last season after a controversial finish.
”This is a big game for us. We can’t look ahead yet to Ireland or France at home,” said Shanklin.
”I have played them three times and lost twice. We know what they are capable of. We can’t get into a dogfight with them.”