Numerous coffees have been shared between Jamie Roberts and Johnny Sexton in the cafes of Paris but all cordialities will be pushed aside when Wales take on Ireland this weekend . Roberts describes Sexton , the Ireland No 10 and his Racing Metro team-mate , as an ‘ angry man ’ who has become one of the world ’ s finest players under the tutorship of Ronan O ’ Gara . Wales will be keeping close tabs on the fly-half on Saturday and Roberts is planning to use his inside knowledge to minimise the 29-year-old ’ s impact at the Millennium Stadium . Racing Metro 's Jamie Roberts is adamant Wales can nullify the threat of club team-mate Johnny Sexton . ‘ We are good mates in Paris and he ’ s a guy who demands high standards , ’ said Roberts . ‘ He ’ s an angry man . The first time I played with him — I remember it well — was on the Lions tour and he was shouting his head off at me and barking orders . It took me by surprise a bit . ‘ He ’ s a bloody good player and a very clever thinker about the game . He ’ s got Ronan O ’ Gara as his mentor in Paris who is passing on a lot of information and helping him develop into a wonderful player . ‘ He is the commander-in-chief of the Ireland team and a guy we need to stay one step ahead of. ’ Ireland 's Johnny Sexton has won his battle to be fit to face Wales in the RBS Six Nations on Saturday . Few have attracted such far-flung praise during this year ’ s RBS Six Nations as Sexton , who has overcome a hamstring injury and is expected to be named in Ireland ’ s starting XV at today ’ s team announcement . The Leinsterman has an all-round repertoire but his kicking has been particularly important within the gameplan of Ireland coach Joe Schmidt . Off the back of a dominant breakdown , Sexton was able to pin back England last week with his accurate footballing skills . It was aperfectly executed strategy and an afternoon that enhanced Schmidt ’ s reputation as one of the game ’ s most thorough tacticians . Ireland often rely on their choke-tackle routine in defence but the Kiwi coach neglected it against England to avoid scrummaging against a powerful pack . It could return on Saturday and Roberts is prepared for more tactical twists in Cardiff . Sexton was in fine form to inspire Ireland to a 19-9 win over England in Dublin last time out . ‘ They are happy to put bombs up in our 22 if they have to , ’ said Roberts . ‘ They always come up with a trick or two , so we have to be prepared for that . You ’ ve seen them have a two- or three-phase set play where they bring their full back near a ruck after phase three or something like that . ‘ There is usually a trick in there . Joe Schmidt is a clever coach ; he is a guy who obviously thinks about the game a lot. ’ Throughout the week , Warren Gatland and his Wales coaching staff have emphasised the importance of playing their own game . That means providing front-foot ball for strike-runners , rather than being kicked into submission by a disciplined Irish set-up . With Sexton ’ s accuracy from the kicking tee , Gatland must also ensure his players keep their penalty count to a minimum , having seen his side concede 37 in the opening rounds . ‘ It ’ s who blinks first but it ’ s also who dares wins , ’ said Roberts . ‘ These big games are like chess and you try to work each other out in the opening exchanges . They are very clever defensively . They pick and choose their rucks . We have got to be very clever in that respect . Wales coach Warren Gatland , at training on Wednesday , is adamant his side must play their own game . ‘ The contact area is more important than it ever has been and so is the referee ’ s interpretation . You watch Ireland ’ s games against France and England and both sides have given them easy outs from their half with cheap penalties , which gave them a strong foothold in opposition territory. ’ Wales are not underestimating their opponents and there have been no verbal barbs from Gatland . He is hoping to reverse a worrying trend in Cardiff , where the Irish have lost only twice in 32 years , with retired back-row Alan Quinlan yesterday writing in his column that ‘ Wales don ’ t scare us like France and England ’ . ‘ That Celtic love and hate is quite evident , ’ said Roberts . ‘ There is always that edge to it . Looking back on a personal note there have been more lows than highs against them and that ’ s something I am quite keen to rectify . ‘ I ’ ll never forget watching Ireland win the Grand Slam in our stadium in 2009 . That is one of those moments that motivates you I suppose . It ’ s something you never want to happen again . ’
Ireland are still on course for a Six Nations Grand Slam . The Irish have won the last two World Cups and will be looking to win another in 2019. Racing Metro team-mates Johnny Sexton and Jamie Roberts will meet . Sexton has overcome a hamstring injury and is expected to start .