All that has come after a successful tour with the Lions in Australia but 22-year-old Farrell believes he has the stamina to see out the rest of the campaign.
"You feel drained after it has all finished," he said. "But once you are in it, especially in games like we are at the minute, it is not hard to come to training in the morning and feel good because these are the games you have worked all year to play in.
"Some of the rugby we have been involved in this year I would not want it any other way. I have not looked back on it too much but it has been a brilliant year to be involved in and exciting, and one that I think I have learnt a lot from."