That was followed by another loss to Australia - 25-23 in Melbourne - but after spending more than ten weeks on the sidelines prior to those games Warburton, who also started the third Test in Sydney - a 20-19 defeat - insists he's now back up to speed.
"I was personally disappointed with the Australia Test series," he told Wales Online.
"It was nowhere near my best performances and I thought I let myself down a bit.
"I am quite hard on myself and I know I have done a lot better in other international matches I have played in.
"I had my five weeks off and I was already looking forward to the new season because I wanted to redeem myself because I knew I was better than that. I was really determined."
And with the autumn internationals in November on the horizon, including a chance of redemption against Australia on December 1, Warburton admits he can't wait to get back to business.
"I still feel like there's work to do and there's probably another 30 per cent in me, in terms of fitness levels and improving my handling skills," he added.
"I have a lot of small goals I am still aiming for and until I reach those I won't really be happy."