Stan Wawrinka believes he has what it takes to get back to playing "great tennis" again, the former world number three said after claiming his first victory in 15 months at the Italian Open on Monday. The 37-year-old Swiss knocked out 14th seed Reilly Opelka 3-6, 7-5, 6-2 in the Rome first round to win for the first time since last year's Australian Open. Playing just his third match of the season, the three-time Grand Slam champion rallied from a set and a break down to beat the 6ft 11 inch (2.1 metre) American and set up a second round with Serbian qualifier Laslo Djere.