Eighth seed Mardy Fish duly progressed to round two of the Australian Open with a straight-sets victory over Luxembourg's Gilles Muller in Melbourne on Monday.
Fish came through 6-4 6-4 6-2 in searing temperatures Down Under.
Fish spent many years in the shadow of countryman Andy Roddick but is now relishing his status as the American number one.
"The goal was always to get into the top 10," Fish said. "The goal was to do well in tournaments and ranking-wise, it never really occurred to me being number one in our country.
"But it feels good, it's a nice title and it's a nice position to be in."
