The British number three raced through the first set against the seventh seed, winning 6-0 in just over half an hour.

But the American, who beat Draper in the second round in Melbourne after losing their two previous meetings, proved stiffer proposition in the second set.

Games remained on serve until Draper cashed in on his second break point to win 6-4.

Dan Evans could not capitalise on a fast start as he went down 6-2 5-7 6-7 to world number 17 Ben Shelton.

The British number two won the first set 6-2, but dropped the second as the American converted his first break point of the match to claim the set.

Evans saved three match points from 0-40 down on his serve in the deciding set and immediately broke Shelton to lead 6-5.

But he was pegged back and, after saving a fourth match point in the tie-break, eventually went down 7-5.