<text>  Robbie Henshaw believes Irelands fledgling centre partnership faces its toughest RBS Six Nations test yet in Wales on Saturday against Jamie Roberts and Jonathan Davies. Connacht battering ram Henshaw has rubbished the suggestions that Warren Gatlands Wales are past their peak that surfaced after the 21-16 home defeat to England. Irelands 21-year-old midfield sensation will pair up with Jared Payne in the centres for just the fifth time in Test action at the Millennium Stadium. Irelands newest sensation Robbie Henshaw left believes Wales will give him the toughest test of his career . Roberts and Davies will combine from the start for the 38th time on Saturday, at the heart of an unchanged line-up following victory over France in Paris. I think it could definitely be the toughest test for me and Jared, said Henshaw of the challenge against Roberts and Davies. Wales are very direct but also they run decoy lines with Roberts coming up, only to throw it out the back and go wide. The centre scored a crucial try during their victory of Six Nations rivals England at the Aviva Stadium . Its going to test us big-time, so weve got to be prepared and stay connected in defence, and just keep our communication up all day. Racing Metro centre Roberts will win his 68th Test cap for Wales this weekend while Clermonts Davies will make it 47 in Cardiffs pivotal Six Nations clash. Ireland can remain on course for a second Grand Slam in seven years with victory on Saturday, with a trip to Scotland still ahead. Jared Payne left celebrates with the scorer as Ireland look in pole position to win the Six Nations . Ruthless boss Joe Schmidt this week omitted veteran centre Gordon DArcy from his 36-man training squad for the remaining two Six Nations contests. DArcy and Brian ODriscoll set a world record 55-Test centre partnership in their wide-ranging careers. Henshaw has long been touted as the now-retired ODriscolls natural successor at outside centre, but has instead found himself replacing DArcy at 12. The Athlone native is gearing up for just his ninth cap in Cardiff, with New Zealand-born Payne in line for his fifth Test bow. The new Irish sensation is being touted as the player to replace legend Brian ODriscoll centre So from boasting the worlds most experienced centre pairing en route to last years Six Nations title, Ireland will concede 101 caps to their midfield rivals against Wales this weekend. Henshaw has vowed he and Payne wont hold back however, buoyed by his first Test try that clinched Irelands 19-9 victory over England on March 1. This Wales team is absolutely not past its peak, said Henshaw. The fact that they are at home and that they play their best rugby at the Millennium, theyre going to cause a massive threat for us. So were going to have to be squeaky clean on the day in terms of our discipline and were going to have to take all the chances we get. Henshaw knows hes in for a tough afternoon when he comes up against the experienced Jamie Roberts . Wales centre Jonathan Davies centre has formed an impressive partnership with Roberts over the years . It might be more open than the England game, but we want to stick to our game plan and follow through on what the coaches want from us. Its not going to be more than a two-score game though. They are not predictable either: they have a lot of different options available to them with Dan Biggar at 10. He gives them a good attacking threat and good aerial skills in the team. Were just going to have to be prepared for anything. I think the Welsh centre partnership is up there with one of the best in the world. Jonny Sexton left is Irelands danger man with some labeling him as the best fly half in the world . They have a really physical threat and massive size in that 10, 12 channel from Jamie Roberts, and then a very good ball player and direct runner in Jonathan Davies. They are going to test us big-time this week but we are fully prepared for what they are going to throw at us. Well have to get off the line quickly in defence and shut down their space and options as early as we can. Well look to get into them early, and we wont hold back. Head coach Joe Schmidt centre is closing in on winning the Grand Slam with Ireland once again . Im constantly learning, growing into it more and more, getting a bit more confident with every game, especially with Jared outside and Johnny Sexton inside. Were building a good relationship there, so at the moment were just looking to build on recent performances. Were feeding off each other at the moment, learning little bits all the time, and growing too. 