"It's been an intense and happy week for the Manchester United family, with two games and two convincing wins at Old Trafford, feeling the extraordinary support from our fans and without conceding a goal," Mata said in his blog.
"The team keeps working very well and we're getting the reward that we deserve so far. The game last Tuesday against Basel was special because it was the club's return to the Champions League.
"The way we won gave us not only three points but plenty of confidence as well. The game was not as easy as the score indicates, but I honestly think that we deserved the victory.
"And the same can be said about this Sunday's game against Everton. We had a very strong start in the first half - by the way, what a superb goal from Antonio [Valencia], the goal of the season so far! - and we kept the 1-0 advantage until the last few minutes, when we managed to score more goals to seal the victory.
"We are happy, for sure, but we keep the euphoria away from the dressing room. Inside, we remain calm, with our feet firmly on the ground. We haven't won anything yet, this is just the beginning and with such a busy schedule there's no time to slow down and relax."