Germany’s Alexander Zverev had his struggles in the Australian Open first round before beating Peruvian qualifier Juan Pablo Varillas 4-6, 6-1, 5-7, 7-6 (7-3), 6-4 on Tuesday. The Olympic champion 25, reached the second round for the seventh time in a row in Melbourne and was the first German man to make it past the first round at this year’s opening grand slam tournament. Seven and a half months after his serious foot injury in the French Open semi-final, Zverev’s lack of match practice was clearly noticeable. After a weak first set, the Hamburg player improved on the hard court, but the worl…