The Ecuador winger has been a hit at Old Trafford since his summer move from Wigan.
“I only scored seven times in my three years at Wigan – and that probably included all the training sessions,” he said in the Daily Express.
“I’m happy with my form but I’m definitely not settling for what I’ve done so far.
“I want to improve, keep learning and achieve a lot more.
“I think fans will see a lot more from me as we progress through the season.”
