Ireland U20 full-back Henry McErlean says they're fully focused on Friday night's Round 4 meeting with Scotland in Glasgow, although he acknowledges that a potential Grand Slam decider against England next week is an "elephant in the room."England lead the championship after three bonus-point wins from three, with defending champions Ireland still very well-placed in second, just one point back.Richie Murphy's side face Scotland at Scotstoun on Friday night (live on RTÉ2 and RTÉ Player), while England welcome France to Bath in the penultimate round of games.And if both sides keep up their winning run, it would set up a mouthwatering winner-takes-all Grand Slam decider at Musgrave Park in Cork on Sunday 19 March."It is always the elephant in the room but as George [teammate George Hadden] was saying we are very moment-focused, looking ahead to the next game there isn't time to get ahead of ourselves," McErlean said."It’s a narrow timespan between each match so you don’t have time to be thinking [about England], we have this week to focus on Scotland, we don’t have any time to be thinking about England."With no games last week, the U20 squad were able to see how they matched up with Andy Farrell's senior squad, training opposite them at Friday's open session at the Aviva Stadium, and coming through it in decent shape, scoring the first try of the mini-game.It's the second time during the championship that the 20s have been able to pick the brains of the senior players, and the former St Michael's College man says they haven't lacked confidence against the world's number one side."In the first training session we played against them in the HPC, we ran that move where Hugo [Keenan] went through the middle [against France].