LONDON, July 5 : Novak Djokovic said he was relieved to have ground down Roman Safiullin and charge into the Wimbledon quarter-finals on Sunday but the perfectionist in him did not enjoy the "ugly" win on Centre Court.The Serb saved set points and then won a tight opening set via a tiebreak in a little over an hour before eventually seeing off his 132nd-ranked opponent in four sets on a blazing day at the All England Club."To be honest, I haven't felt really great on the court, so I was relieved to get out of it and get a win," Djokovic said in his press conference."Satisfaction and enjoyment weren't part of today's win. Of course, I'm relieved and happy to win it, but I haven't enjoyed it. Hopefully the next match will be better in that sense." Djokovic said the constant pressure from Rus