If you have forgotten Juventus have Ronaldo playing for them who knows Atletico Madrid well, and hell try and win it on his own if required.
Ronaldo has a history in scoring goals against Athletico and I do hope it continues, though there is every livelihood that it may not come into play in this game, this sort of match looks so much like a draw to me, as the both teams would be rather too careful so as not to kick off their UCL season on a bad note.
I think this is the biggest match of the first matchday and it's the one everyone is eager to watch, I'll be predicting this one in favor of Athletico, I think they have a slight edge over juve this season, still early though, but I believe they'll win: 2:1.