A video of his press conference, he looks really cute with his mini-dreads, but it doesn't seem to be very comfortable!
He's happy to have won, but he knows he didn't play great tennis.
It was a close match, he was a bit lucky too.
He wasn't stressed before the match, he just got tight during the match because he was focussing too much on the wrong strategy (he wanted to make Karlovic play long rallies) and he ended up playing very short, without much power, it wasn't so good.
And then he speaks in great detail about Federer's match - he was sure Fed was going to come back and win, it was not only poorly played by RRH, he also found impressive how Fed played some points, he's a great warrior and it will be very tough tomorrow, etc.