Ireland's hunt for a Six Nations Grand Slam is on after the world's top-ranked team overcame Italy 34-20 in an entertaining encounter in Rome on Saturday.Mack Hansen scored two tries with James Ryan, Hugo Kennan and Bundee Aki also dotting down to ensure that the Irish have taken 15 points from their three matches in this year's tournament.Ross Byrne, who played in place of captain Johnny Sexton, kicked 14 points in a win which for long spells looked far from guaranteed.Andy Farrell's side are five points clear at the top of the Six Nations standings ahead of closest rivals Scotland's showdown against France at the Stade de France on Sunday.Italy stay on a single point in the table, one in front of troubled Wales who host England later on Saturday.Azzurri coach Kieran Crowley and the country's rugby federation said before the tournament that they were targeting two wins this year but they now have their work cut out if they want to reach that objective.Grand Slam still on for Ireland! #GuinnessSixNations #ITAvIRE pic.twitter.com/cAmu0V4po5Italy host Wales, beaten by the Azzurri at the end of last year's Six Nations, in a fortnight's time before travelling to Murrayfield to take on Scotland a week later as they try to avoid yet another wooden spoon.Crowley's young team caused Ireland problems with their own expansive style of rugby and scored tries through Stephen Varney and Pierre Bruno, with the returning flyhalf Paolo Garbisi kicking 10 points.Ireland made six changes from the team which beat France two weeks ago and had to battle their way past the Italians, but looked like they were going to run away with the match early on as James Lowe just failed to dot down under pressure from Ange Capuozzo.Seconds later Lowe was